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30,007,116
EP-998
Erdős Problem #998: Analysis, Diophantine Approximation
Let $\alpha$ be an irrational number. Is it true that if, for all large $n$,\[\#\{ 1\leq m\leq n: \{ \alpha m\} \in [u,v)\} = n(v-u)+O(1)\]then $u=\{\alpha k\}$ and $v=\{\alpha \ell\}$ for some integers $k$ and $\ell$?
Erdős Problems (#998, https://www.erdosproblems.com/998). Maintainer status: PROVED.
3
solved
Paul Erdős
null
8
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 8, "name": "analysis", "display_name": "Analysis", "description": "Limits, continuity, calculus, and function theory.", "slug": "analysis", "order_index": 8, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/998", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "proved" }
null
null
null
null
[ "erdos-problems", "analysis", "diophantine-approximation" ]
null
null
null
null
https://www.erdosproblems.com/998
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,117
EP-999
Erdős Problem #999: Number Theory, Diophantine Approximation
For any function $f:\mathbb{N}\to \mathbb{N}$ the property that, for almost all $\alpha$\[\left\lvert \alpha-\frac{p}{q}\right\rvert < \frac{f(q)}{q}\]has infinitely many solutions with $(p,q)=1$, is equivalent to\[\sum_{q\geq 1}\phi(q)\frac{f(q)}{q}=\infty.\]
Erdős Problems (#999, https://www.erdosproblems.com/999). Maintainer status: PROVED. Duffin-Schaeffer conjecture Formalized in Lean (google-deepmind/formal-conjectures, ErdosProblems.999).
3
solved
Paul Erdős
null
1
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 1, "name": "number_theory", "display_name": "Number Theory", "description": "Properties of integers, prime numbers, Diophantine equations.", "slug": "number-theory", "order_index": 1, "created_at": "2026-07-31T15:26:25.670Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/999", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "proved" }
null
null
null
Duffin-Schaeffer conjecture
[ "erdos-problems", "number-theory", "diophantine-approximation" ]
null
null
null
null
https://www.erdosproblems.com/999
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,118
EP-1000
Erdős Problem #1000: Number Theory, Diophantine Approximation
Let $A=\{n_1<n_2<\cdots\}$ be an infinite sequence of integers, and let $\phi_A(k)$ count the number of $1\leq m\leq n_k$ such that the fraction $\frac{m}{n_k}$ does not have denominator $n_j$ for $j<k$ when written in lowest form; equivalently,\[\frac{n_k}{(m,n_k)}\neq n_j\]for all $1\leq j<k$. Is there a sequence $A...
Erdős Problems (#1000, https://www.erdosproblems.com/1000). Maintainer status: PROVED (LEAN). Formalized in Lean (google-deepmind/formal-conjectures, ErdosProblems.1000).
3
solved
Paul Erdős
null
1
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 1, "name": "number_theory", "display_name": "Number Theory", "description": "Properties of integers, prime numbers, Diophantine equations.", "slug": "number-theory", "order_index": 1, "created_at": "2026-07-31T15:26:25.670Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1000", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "proved (Lean)" }
null
null
null
null
[ "erdos-problems", "number-theory", "diophantine-approximation" ]
null
null
null
null
https://www.erdosproblems.com/1000
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,119
EP-1001
Erdős Problem #1001: Number Theory, Diophantine Approximation
Let $S(N,A,c)$ be the measure of the set of those $\alpha\in (0,1)$ such that\[\left\lvert \alpha-\frac{x}{y}\right\rvert< \frac{A}{y^2}\]for some $N\leq y\leq cN$ and $(x,y)=1$. Does\[\lim_{N\to \infty}S(N,A,c)=f(A,c)\]exist? What is its explicit form?
Erdős Problems (#1001, https://www.erdosproblems.com/1001). Maintainer status: SOLVED.
3
solved
Paul Erdős
null
1
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 1, "name": "number_theory", "display_name": "Number Theory", "description": "Properties of integers, prime numbers, Diophantine equations.", "slug": "number-theory", "order_index": 1, "created_at": "2026-07-31T15:26:25.670Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1001", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "solved" }
null
null
null
null
[ "erdos-problems", "number-theory", "diophantine-approximation" ]
null
null
null
null
https://www.erdosproblems.com/1001
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,120
EP-1006
Erdős Problem #1006: Graph Theory, Cycles
Let $G$ be a graph with girth $>4$ (that is, it contains no cycles of length $3$ or $4$). Can the edges of $G$ always be directed such that there is no directed cycle, and reversing the direction of any edge also creates no directed cycle?
Erdős Problems (#1006, https://www.erdosproblems.com/1006). Maintainer status: DISPROVED.
3
solved
Paul Erdős
null
3
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 3, "name": "graph_theory", "display_name": "Graph Theory", "description": "Problems involving graphs, networks, and their properties.", "slug": "graph-theory", "order_index": 3, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1006", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "disproved" }
null
null
null
null
[ "erdos-problems", "graph-theory", "cycles" ]
null
null
null
null
https://www.erdosproblems.com/1006
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,121
EP-1007
Erdős Problem #1007: Graph Theory
The dimension of a graph $G$ is the minimal $n$ such that $G$ can be embedded in $\mathbb{R}^n$ such that every edge of $G$ is a unit line segment. What is the smallest number of edges in a graph with dimension $4$?
Erdős Problems (#1007, https://www.erdosproblems.com/1007). Maintainer status: SOLVED (LEAN). Formalized in Lean (google-deepmind/formal-conjectures, ErdosProblems.1007).
3
solved
Paul Erdős
null
3
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 3, "name": "graph_theory", "display_name": "Graph Theory", "description": "Problems involving graphs, networks, and their properties.", "slug": "graph-theory", "order_index": 3, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1007", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "solved (Lean)" }
null
null
null
null
[ "erdos-problems", "graph-theory" ]
null
null
null
null
https://www.erdosproblems.com/1007
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,122
EP-1008
Erdős Problem #1008: Graph Theory, Cycles
Does every graph with $m$ edges contain a subgraph with $\gg m^{2/3}$ edges which contains no $C_4$?
Erdős Problems (#1008, https://www.erdosproblems.com/1008). Maintainer status: PROVED (LEAN). Formalized in Lean (google-deepmind/formal-conjectures, ErdosProblems.1008).
3
solved
Paul Erdős
null
3
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 3, "name": "graph_theory", "display_name": "Graph Theory", "description": "Problems involving graphs, networks, and their properties.", "slug": "graph-theory", "order_index": 3, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1008", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "proved (Lean)" }
null
null
null
null
[ "erdos-problems", "graph-theory", "cycles" ]
null
null
null
null
https://www.erdosproblems.com/1008
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,123
EP-1009
Erdős Problem #1009: Graph Theory
Is it true that, for every $c>0$, there exists $f(c)$ such that every graph on $n$ vertices with at least $\lfloor n^2/4\rfloor+k$ edges, where $k<c n$, contains at least $k-f(c)$ many edge disjoint triangles?
Erdős Problems (#1009, https://www.erdosproblems.com/1009). Maintainer status: PROVED. Formalized in Lean (google-deepmind/formal-conjectures, ErdosProblems.1009).
3
solved
Paul Erdős
null
3
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 3, "name": "graph_theory", "display_name": "Graph Theory", "description": "Problems involving graphs, networks, and their properties.", "slug": "graph-theory", "order_index": 3, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1009", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "proved" }
null
null
null
null
[ "erdos-problems", "graph-theory" ]
null
null
null
null
https://www.erdosproblems.com/1009
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,124
EP-1010
Erdős Problem #1010: Graph Theory
Let $t<\lfloor n/2\rfloor$. Does every graph on $n$ vertices with $\lfloor n^2/4\rfloor+t$ edges contain at least $t\lfloor n/2\rfloor$ triangles?
Erdős Problems (#1010, https://www.erdosproblems.com/1010). Maintainer status: PROVED. Formalized in Lean (google-deepmind/formal-conjectures, ErdosProblems.1010).
3
solved
Paul Erdős
null
3
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 3, "name": "graph_theory", "display_name": "Graph Theory", "description": "Problems involving graphs, networks, and their properties.", "slug": "graph-theory", "order_index": 3, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1010", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "proved" }
null
null
null
null
[ "erdos-problems", "graph-theory" ]
null
null
null
null
https://www.erdosproblems.com/1010
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,125
EP-1012
Erdős Problem #1012: Graph Theory
Let $k\geq 0$. Let $f(k)$ be such that every graph on $n\geq f(k)$ vertices with at least $\binom{n-k-1}{2}+\binom{k+2}{2}+1$ edges contains a cycle on $n-k$ vertices. Determine or estimate $f(k)$.
Erdős Problems (#1012, https://www.erdosproblems.com/1012). Maintainer status: SOLVED.
3
solved
Paul Erdős
null
3
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 3, "name": "graph_theory", "display_name": "Graph Theory", "description": "Problems involving graphs, networks, and their properties.", "slug": "graph-theory", "order_index": 3, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1012", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "solved" }
null
null
null
null
[ "erdos-problems", "graph-theory" ]
null
null
null
null
https://www.erdosproblems.com/1012
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,126
EP-1015
Erdős Problem #1015: Graph Theory, Ramsey Theory
Let $f(t)$ be minimal such that, in any two-colouring of the edges of $K_n$, the edges can be partitioned into vertex disjoint monochromatic copies of $K_t$ (not necessarily the same colour) with at most $f(t)$ vertices remaining. Estimate $f(t)$. In particular, is it true that $f(t)^{1/t}\to 1$? Is it true that $f(t)...
Erdős Problems (#1015, https://www.erdosproblems.com/1015). Maintainer status: SOLVED.
3
solved
Paul Erdős
null
3
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 3, "name": "graph_theory", "display_name": "Graph Theory", "description": "Problems involving graphs, networks, and their properties.", "slug": "graph-theory", "order_index": 3, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1015", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "solved" }
null
null
null
null
[ "erdos-problems", "graph-theory", "ramsey-theory" ]
null
null
null
null
https://www.erdosproblems.com/1015
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,127
EP-1018
Erdős Problem #1018: Graph Theory, Planar Graphs
Let $\epsilon>0$. Is there a constant $C_\epsilon$ such that, for all large $n$, every graph on $n$ vertices with at least $n^{1+\epsilon}$ edges must contain a subgraph on at most $C_\epsilon$ vertices which is non-planar?
Erdős Problems (#1018, https://www.erdosproblems.com/1018). Maintainer status: SOLVED (LEAN).
3
solved
Paul Erdős
null
3
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 3, "name": "graph_theory", "display_name": "Graph Theory", "description": "Problems involving graphs, networks, and their properties.", "slug": "graph-theory", "order_index": 3, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1018", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "solved (Lean)" }
null
null
null
null
[ "erdos-problems", "graph-theory", "planar-graphs" ]
null
null
null
null
https://www.erdosproblems.com/1018
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,128
EP-1019
Erdős Problem #1019: Graph Theory, Planar Graphs
A planar graph on $n$ vertices with $3n-6$ edges (the maximum possible) is called saturated. Does every graph on $n$ vertices with $\lfloor n^2/4\rfloor+\lfloor \frac{n+1}{2}\rfloor$ edges contain a saturated planar graph with $>3$ vertices?
Erdős Problems (#1019, https://www.erdosproblems.com/1019). Maintainer status: PROVED (LEAN).
3
solved
Paul Erdős
null
3
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 3, "name": "graph_theory", "display_name": "Graph Theory", "description": "Problems involving graphs, networks, and their properties.", "slug": "graph-theory", "order_index": 3, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1019", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "proved (Lean)" }
null
null
null
null
[ "erdos-problems", "graph-theory", "planar-graphs" ]
null
null
null
null
https://www.erdosproblems.com/1019
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,129
EP-1020
Erdős Problem #1020:
Let $f(n;r,k)$ be the maximal number of edges in an $r$-uniform hypergraph which contains no set of $k$ many independent edges. For all $r\geq 3$,\[f(n;r,k)=\max\left(\binom{rk-1}{r}, \binom{n}{r}-\binom{n-k+1}{r}\right).\]
Erdős Problems (#1020, https://www.erdosproblems.com/1020). Maintainer status: FALSIFIABLE. Erdős matching conjecture Formalized in Lean (google-deepmind/formal-conjectures, ErdosProblems.1020).
3
open
Paul Erdős
null
3
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 3, "name": "graph_theory", "display_name": "Graph Theory", "description": "Problems involving graphs, networks, and their properties.", "slug": "graph-theory", "order_index": 3, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1020", "checked_at": "2026-10-16", "kind": "open", "evidence": "maintained_source", "maintainer_status": "falsifiable" }
null
null
null
Erdős matching conjecture
[ "erdos-problems", "graph-theory", "hypergraphs" ]
null
null
null
null
https://www.erdosproblems.com/1020
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,130
EP-1023
Erdős Problem #1023: Combinatorics
Let $F(n)$ be the maximal size of a family of subsets of $\{1,\ldots,n\}$ such that no set in this family is the union of other members of the family. Is it true that there is a constant $c>0$ such that\[F(n)\sim c \frac{2^n}{n^{1/2}}?\]
Erdős Problems (#1023, https://www.erdosproblems.com/1023). Maintainer status: SOLVED (LEAN). OEIS: A347025. Formalized in Lean (google-deepmind/formal-conjectures, ErdosProblems.1023).
3
solved
Paul Erdős
null
2
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 2, "name": "combinatorics", "display_name": "Combinatorics", "description": "Counting problems, graph theory, discrete structures.", "slug": "combinatorics", "order_index": 2, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1023", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "solved (Lean)" }
null
null
null
null
[ "erdos-problems", "combinatorics" ]
null
null
null
null
https://www.erdosproblems.com/1023
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,131
EP-1024
Erdős Problem #1024: Estimate $f(n)$
Let $f(n)$ be such that every $3$-uniform linear hypergraph on $n$ vertices contains an independent set on $f(n)$ vertices. Estimate $f(n)$.
Erdős Problems (#1024, https://www.erdosproblems.com/1024). Maintainer status: SOLVED. Formalized in Lean (google-deepmind/formal-conjectures, ErdosProblems.1024).
3
solved
Paul Erdős
null
3
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 3, "name": "graph_theory", "display_name": "Graph Theory", "description": "Problems involving graphs, networks, and their properties.", "slug": "graph-theory", "order_index": 3, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1024", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "solved" }
null
null
null
null
[ "erdos-problems", "graph-theory", "hypergraphs" ]
null
null
null
null
https://www.erdosproblems.com/1024
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,132
EP-1025
Erdős Problem #1025: Combinatorics
Let $f$ be a function from all pairs of elements in $\{1,\ldots,n\}$ to $\{1,\ldots,n\}$ such that $f(x,y)\neq x$ and $\neq y$ for all $x,y$. We call $X\subseteq \{1,\ldots,n\}$ independent if whenever $x,y\in X$ we have $f(x,y)\not\in X$. Let $g(n)$ be such that, in every function $f$, there is an independent set of ...
Erdős Problems (#1025, https://www.erdosproblems.com/1025). Maintainer status: SOLVED (LEAN). Formalized in Lean (google-deepmind/formal-conjectures, ErdosProblems.1025).
3
solved
Paul Erdős
null
2
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 2, "name": "combinatorics", "display_name": "Combinatorics", "description": "Counting problems, graph theory, discrete structures.", "slug": "combinatorics", "order_index": 2, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1025", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "solved (Lean)" }
null
null
null
null
[ "erdos-problems", "combinatorics" ]
null
null
null
null
https://www.erdosproblems.com/1025
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,133
EP-1026
Erdős Problem #1026: Combinatorics
Let $x_1,\ldots,x_n$ be a sequence of distinct real numbers. Determine\[\max\left(\sum x_{i_r}\right),\]where the maximum is taken over all monotonic subsequences.
Erdős Problems (#1026, https://www.erdosproblems.com/1026). Maintainer status: SOLVED (LEAN). OEIS: A391431, A391490. Formalized in Lean (google-deepmind/formal-conjectures, ErdosProblems.1026).
3
solved
Paul Erdős
null
2
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 2, "name": "combinatorics", "display_name": "Combinatorics", "description": "Counting problems, graph theory, discrete structures.", "slug": "combinatorics", "order_index": 2, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1026", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "solved (Lean)" }
null
null
null
null
[ "erdos-problems", "combinatorics" ]
null
null
null
null
https://www.erdosproblems.com/1026
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,134
EP-1027
Erdős Problem #1027: Combinatorics
Let $c>0$, and let $n$ be sufficiently large depending on $c$. Suppose that $\mathcal{F}$ is a family of at most $c2^n$ many finite sets of size $n$. Let $X=\cup_{A\in \mathcal{F}}A$. Must there exist $\gg_c 2^{\lvert X\rvert}$ many sets $B\subset X$ which intersect every set in $\mathcal{F}$, yet contain none of them...
Erdős Problems (#1027, https://www.erdosproblems.com/1027). Maintainer status: PROVED. Formalized in Lean (google-deepmind/formal-conjectures, ErdosProblems.1027).
3
solved
Paul Erdős
null
2
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 2, "name": "combinatorics", "display_name": "Combinatorics", "description": "Counting problems, graph theory, discrete structures.", "slug": "combinatorics", "order_index": 2, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1027", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "proved" }
null
null
null
null
[ "erdos-problems", "combinatorics" ]
null
null
null
null
https://www.erdosproblems.com/1027
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,135
EP-1028
Erdős Problem #1028: Graph Theory, Discrepancy
Let\[H(n)=\min_f \max_{X\subseteq \{1,\ldots,n\}} \left\lvert \sum_{x\neq y\in X} f(x,y)\right\rvert,\]where $f$ ranges over all functions $f:X^2\to \{-1,1\}$. Estimate $H(n)$.
Erdős Problems (#1028, https://www.erdosproblems.com/1028). Maintainer status: SOLVED (LEAN). Formalized in Lean (google-deepmind/formal-conjectures, ErdosProblems.1028).
3
solved
Paul Erdős
null
8
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 8, "name": "analysis", "display_name": "Analysis", "description": "Limits, continuity, calculus, and function theory.", "slug": "analysis", "order_index": 8, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1028", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "solved (Lean)" }
null
null
null
null
[ "erdos-problems", "graph-theory", "discrepancy" ]
null
null
null
null
https://www.erdosproblems.com/1028
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,136
EP-1031
Erdős Problem #1031: Graph Theory
If $G$ is a graph on $n$ vertices which contains no trivial (empty or complete) subgraph on $\geq 10\log n$ many vertices, then must $G$ contain an induced non-trivial regular subgraph on $\gg \log n$ many vertices?
Erdős Problems (#1031, https://www.erdosproblems.com/1031). Maintainer status: PROVED.
3
solved
Paul Erdős
null
3
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 3, "name": "graph_theory", "display_name": "Graph Theory", "description": "Problems involving graphs, networks, and their properties.", "slug": "graph-theory", "order_index": 3, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1031", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "proved" }
null
null
null
null
[ "erdos-problems", "graph-theory" ]
null
null
null
null
https://www.erdosproblems.com/1031
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,137
EP-1034
Erdős Problem #1034: Graph Theory
Let $G$ be a graph on $n$ vertices with $>n^2/4$ many edges. Must there be a triangle $T$ in $G$ and vertices $y_1,\ldots,y_t$, where $t>(\frac{1}{2}-o(1))n$, such that every vertex is joined to at least two vertices of $T$?
Erdős Problems (#1034, https://www.erdosproblems.com/1034). Maintainer status: DISPROVED (LEAN). Formalized in Lean (google-deepmind/formal-conjectures, ErdosProblems.1034).
3
solved
Paul Erdős
null
3
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 3, "name": "graph_theory", "display_name": "Graph Theory", "description": "Problems involving graphs, networks, and their properties.", "slug": "graph-theory", "order_index": 3, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1034", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "disproved (Lean)" }
null
null
null
null
[ "erdos-problems", "graph-theory" ]
null
null
null
null
https://www.erdosproblems.com/1034
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,138
EP-1036
Erdős Problem #1036: Graph Theory
Let $G$ be a graph on $n$ vertices which does not contain a trivial (empty or complete) graph on more than $c\log n$ vertices. Must $G$ contain at least $2^{\Omega_c(n)}$ many induced subgraphs which are not pairwise isomorphic?
Erdős Problems (#1036, https://www.erdosproblems.com/1036). Maintainer status: PROVED (LEAN). Formalized in Lean (google-deepmind/formal-conjectures, ErdosProblems.1036).
3
solved
Paul Erdős
null
3
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 3, "name": "graph_theory", "display_name": "Graph Theory", "description": "Problems involving graphs, networks, and their properties.", "slug": "graph-theory", "order_index": 3, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1036", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "proved (Lean)" }
null
null
null
null
[ "erdos-problems", "graph-theory" ]
null
null
null
null
https://www.erdosproblems.com/1036
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,139
EP-1037
Erdős Problem #1037: Graph Theory
Let $G$ be a graph on $n$ vertices in which every degree occurs at most twice, and the number of distinct degree is $>(\frac{1}{2}+\epsilon)n$. Must $G$ contain a trivial (empty or complete) subgraph of size 'much larger' than $\log n$?
Erdős Problems (#1037, https://www.erdosproblems.com/1037). Maintainer status: DISPROVED (LEAN). Formalized in Lean (google-deepmind/formal-conjectures, ErdosProblems.1037).
3
solved
Paul Erdős
null
3
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 3, "name": "graph_theory", "display_name": "Graph Theory", "description": "Problems involving graphs, networks, and their properties.", "slug": "graph-theory", "order_index": 3, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1037", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "disproved (Lean)" }
null
null
null
null
[ "erdos-problems", "graph-theory" ]
null
null
null
null
https://www.erdosproblems.com/1037
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,140
EP-1041
Erdős Problem #1041: with $\lvert z_i\rvert < 1$ for all $i$
Let $f(z)=\prod_{i=1}^n(z-z_i)\in \mathbb{C}[z]$ with $\lvert z_i\rvert < 1$ for all $i$. Must there always exist a path of length less than $2$ in\[\{z: \lvert f(z)\rvert < 1\}\]which connects two of the roots of $f$?
Erdős Problems (#1041, https://www.erdosproblems.com/1041). Maintainer status: FALSIFIABLE. Formalized in Lean (google-deepmind/formal-conjectures, ErdosProblems.1041).
3
open
Paul Erdős
null
8
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 8, "name": "analysis", "display_name": "Analysis", "description": "Limits, continuity, calculus, and function theory.", "slug": "analysis", "order_index": 8, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1041", "checked_at": "2026-10-16", "kind": "open", "evidence": "maintained_source", "maintainer_status": "falsifiable" }
null
null
null
null
[ "erdos-problems", "analysis", "polynomials" ]
null
null
null
null
https://www.erdosproblems.com/1041
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,141
EP-1042
Erdős Problem #1042:
Let $F\subset\mathbb{C}$ be a closed set of transfinite diameter $1$ which is not contained in any closed disc of radius $1$. If $f(z)=\prod_{i=1}^n(z-z_i)\in\mathbb{C}[x]$ with all $z_i\in F$ then can\[\{ z: \lvert f(z)\rvert < 1\}\]have $n$ connected components? If the transfinite diameter of $F$ is $<1$ then must ...
Erdős Problems (#1042, https://www.erdosproblems.com/1042). Maintainer status: PROVED.
3
solved
Paul Erdős
null
8
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 8, "name": "analysis", "display_name": "Analysis", "description": "Limits, continuity, calculus, and function theory.", "slug": "analysis", "order_index": 8, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1042", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "proved" }
null
null
null
null
[ "erdos-problems", "analysis" ]
null
null
null
null
https://www.erdosproblems.com/1042
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,142
EP-1043
Erdős Problem #1043: Analysis
Let $f\in \mathbb{C}[x]$ be a monic non-constant polynomial. Must there exist a straight line $\ell$ such that the projection of\[\{ z: \lvert f(z)\rvert\leq 1\}\]onto $\ell$ has measure at most $2$?
Erdős Problems (#1043, https://www.erdosproblems.com/1043). Maintainer status: DISPROVED (LEAN). Formalized in Lean (google-deepmind/formal-conjectures, ErdosProblems.1043).
3
solved
Paul Erdős
null
8
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 8, "name": "analysis", "display_name": "Analysis", "description": "Limits, continuity, calculus, and function theory.", "slug": "analysis", "order_index": 8, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1043", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "disproved (Lean)" }
null
null
null
null
[ "erdos-problems", "analysis" ]
null
null
null
null
https://www.erdosproblems.com/1043
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,143
EP-1044
Erdős Problem #1044: Analysis
Let $f(z)=\prod_{i=1}^n(z-z_i)\in\mathbb{C}[x]$ where $\lvert z_i\rvert\leq 1$ for all $i$. If $\Lambda(f)$ is the maximum of the lengths of the boundaries of the connected components of\[\{ z: \lvert f(z)\rvert<1\}\]then determine the infimum of $\Lambda(f)$.
Erdős Problems (#1044, https://www.erdosproblems.com/1044). Maintainer status: SOLVED (LEAN). Formalized in Lean (google-deepmind/formal-conjectures, ErdosProblems.1044).
3
solved
Paul Erdős
null
8
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 8, "name": "analysis", "display_name": "Analysis", "description": "Limits, continuity, calculus, and function theory.", "slug": "analysis", "order_index": 8, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1044", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "solved (Lean)" }
null
null
null
null
[ "erdos-problems", "analysis" ]
null
null
null
null
https://www.erdosproblems.com/1044
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,144
EP-1045
Erdős Problem #1045: Analysis
Let $z_1,\ldots,z_n\in \mathbb{C}$ with $\lvert z_i-z_j\rvert\leq 2$ for all $i,j$, and\[\Delta(z_1,\ldots,z_n)=\prod_{i\neq j}\lvert z_i-z_j\rvert.\]What is the maximum possible value of $\Delta$? Is it maximised by taking the $z_i$ to be the vertices of a regular polygon?
Erdős Problems (#1045, https://www.erdosproblems.com/1045). Maintainer status: OPEN.
3
open
Paul Erdős
null
8
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 8, "name": "analysis", "display_name": "Analysis", "description": "Limits, continuity, calculus, and function theory.", "slug": "analysis", "order_index": 8, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1045", "checked_at": "2026-10-16", "kind": "open", "evidence": "maintained_source", "maintainer_status": "open" }
null
null
null
null
[ "erdos-problems", "analysis" ]
null
null
null
null
https://www.erdosproblems.com/1045
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,145
EP-1046
Erdős Problem #1046: \]If $E$ is connected then is $E$ contained in a disc of radius $2$?
Let $f\in \mathbb{C}[x]$ be a monic polynomial and\[E=\{ z: \lvert f(z)\rvert <1\}.\]If $E$ is connected then is $E$ contained in a disc of radius $2$?
Erdős Problems (#1046, https://www.erdosproblems.com/1046). Maintainer status: DISPROVED. Formalized in Lean (google-deepmind/formal-conjectures, ErdosProblems.1046).
3
solved
Paul Erdős
null
8
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 8, "name": "analysis", "display_name": "Analysis", "description": "Limits, continuity, calculus, and function theory.", "slug": "analysis", "order_index": 8, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1046", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "disproved" }
null
null
null
null
[ "erdos-problems", "analysis" ]
null
null
null
null
https://www.erdosproblems.com/1046
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,146
EP-1047
Erdős Problem #1047: Analysis
Let $f\in \mathbb{C}[x]$ be a monic polynomial with $m$ distinct roots, and let $c>0$ be a constant small enough such that $\{ z: \lvert f(z)\rvert\leq c\}$ has $m$ distinct connected components. Must all these components be convex?
Erdős Problems (#1047, https://www.erdosproblems.com/1047). Maintainer status: DISPROVED (LEAN). Formalized in Lean (google-deepmind/formal-conjectures, ErdosProblems.1047).
3
solved
Paul Erdős
null
8
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 8, "name": "analysis", "display_name": "Analysis", "description": "Limits, continuity, calculus, and function theory.", "slug": "analysis", "order_index": 8, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1047", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "disproved (Lean)" }
null
null
null
null
[ "erdos-problems", "analysis" ]
null
null
null
null
https://www.erdosproblems.com/1047
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,147
EP-1048
Erdős Problem #1048: Analysis
If $f\in \mathbb{C}[x]$ is a monic polynomial with all roots satisfying $\lvert z\rvert \leq r$ for some $r<2$, then must\[\{ z: \lvert f(z)\rvert <1\}\]have a connected component with diameter $>2-r$?
Erdős Problems (#1048, https://www.erdosproblems.com/1048). Maintainer status: DISPROVED (LEAN). Formalized in Lean (google-deepmind/formal-conjectures, ErdosProblems.1048).
3
solved
Paul Erdős
null
8
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 8, "name": "analysis", "display_name": "Analysis", "description": "Limits, continuity, calculus, and function theory.", "slug": "analysis", "order_index": 8, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1048", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "disproved (Lean)" }
null
null
null
null
[ "erdos-problems", "analysis" ]
null
null
null
null
https://www.erdosproblems.com/1048
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,148
EP-1050
Erdős Problem #1050: Is\[\sum_{n=1}^\infty \frac{1}{2^n-3}\]irrational?
Is\[\sum_{n=1}^\infty \frac{1}{2^n-3}\]irrational?
Erdős Problems (#1050, https://www.erdosproblems.com/1050). Maintainer status: PROVED (LEAN). OEIS: A331372. Formalized in Lean (google-deepmind/formal-conjectures, ErdosProblems.1050).
3
solved
Paul Erdős
null
1
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 1, "name": "number_theory", "display_name": "Number Theory", "description": "Properties of integers, prime numbers, Diophantine equations.", "slug": "number-theory", "order_index": 1, "created_at": "2026-07-31T15:26:25.670Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1050", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "proved (Lean)" }
null
null
null
null
[ "erdos-problems", "irrationality" ]
null
null
null
null
https://www.erdosproblems.com/1050
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,149
EP-1058
Erdős Problem #1058: Number Theory
Let $2=p_1<p_2<\cdots$ be the sequence of prime numbers. Are there only finitely many $n$ such that $n\in [p_{k-1},p_k)$ and the only primes dividing $n!+1$ are $p_{k}$ and $p_{k+1}$?
Erdős Problems (#1058, https://www.erdosproblems.com/1058). Maintainer status: PROVED. Formalized in Lean (google-deepmind/formal-conjectures, ErdosProblems.1058).
3
solved
Paul Erdős
null
1
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 1, "name": "number_theory", "display_name": "Number Theory", "description": "Properties of integers, prime numbers, Diophantine equations.", "slug": "number-theory", "order_index": 1, "created_at": "2026-07-31T15:26:25.670Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1058", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "proved" }
null
null
null
null
[ "erdos-problems", "number-theory" ]
null
null
null
null
https://www.erdosproblems.com/1058
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,150
EP-1064
Erdős Problem #1064: Number Theory
Prove that $\phi(n)>\phi(n-\phi(n))$ for almost all $n$, but that $\phi(n)<\phi(n-\phi(n))$ for infinitely many $n$, where $\phi$ is Euler's totient function.
Erdős Problems (#1064, https://www.erdosproblems.com/1064). Maintainer status: PROVED. OEIS: A051488, A051487. Formalized in Lean (google-deepmind/formal-conjectures, ErdosProblems.1064).
3
solved
Paul Erdős
null
1
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 1, "name": "number_theory", "display_name": "Number Theory", "description": "Properties of integers, prime numbers, Diophantine equations.", "slug": "number-theory", "order_index": 1, "created_at": "2026-07-31T15:26:25.670Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1064", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "proved" }
null
null
null
null
[ "erdos-problems", "number-theory" ]
null
null
null
null
https://www.erdosproblems.com/1064
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,151
EP-1067
Erdős Problem #1067: Graph Theory, Set Theory
Does every graph with chromatic number $\aleph_1$ contain an infinitely connected subgraph with chromatic number $\aleph_1$?
Erdős Problems (#1067, https://www.erdosproblems.com/1067). Maintainer status: DISPROVED (LEAN). Formalized in Lean (google-deepmind/formal-conjectures, ErdosProblems.1067).
3
solved
Paul Erdős
null
3
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 3, "name": "graph_theory", "display_name": "Graph Theory", "description": "Problems involving graphs, networks, and their properties.", "slug": "graph-theory", "order_index": 3, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1067", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "disproved (Lean)" }
null
null
null
null
[ "erdos-problems", "graph-theory", "set-theory" ]
null
null
null
null
https://www.erdosproblems.com/1067
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,152
EP-1069
Erdős Problem #1069: Geometry
Given any $n$ points in $\mathbb{R}^2$, the number of $k$-rich lines (lines which contain $\geq k$ of the points) is, provided $k\leq n^{1/2}$,\[\ll \frac{n^2}{k^3}.\]
Erdős Problems (#1069, https://www.erdosproblems.com/1069). Maintainer status: SOLVED.
3
solved
Paul Erdős
null
6
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 6, "name": "geometry", "display_name": "Geometry", "description": "Euclidean and non-Euclidean geometry, geometric structures.", "slug": "geometry", "order_index": 6, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1069", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "solved" }
null
null
null
null
[ "erdos-problems", "geometry" ]
null
null
null
null
https://www.erdosproblems.com/1069
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,153
EP-1076
Erdős Problem #1076: Hypergraphs
Let $k\geq 5$ and let $\mathcal{F}_k$ be the family of all $3$-uniform hypergraphs with $k$ vertices and $k-2$ edges. Is it true that\[\mathrm{ex}_3(n,\mathcal{F}_k)\sim \frac{n^2}{6}?\]
Erdős Problems (#1076, https://www.erdosproblems.com/1076). Maintainer status: PROVED.
3
solved
Paul Erdős
null
2
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 2, "name": "combinatorics", "display_name": "Combinatorics", "description": "Counting problems, graph theory, discrete structures.", "slug": "combinatorics", "order_index": 2, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1076", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "proved" }
null
null
null
null
[ "erdos-problems", "hypergraphs" ]
null
null
null
null
https://www.erdosproblems.com/1076
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,154
EP-1077
Erdős Problem #1077: Graph Theory
We call a graph $D$-balanced (or $D$-almost-regular) if the maximum degree is at most $D$ times the minimum degree. Let $\epsilon,\alpha>0$ and $D$ and $n$ be sufficiently large. If $G$ is a graph on $n$ vertices with at least $n^{1+\alpha}$ edges, then must $G$ contain a $D$-balanced subgraph on $m>n^{1-\alpha}$ vert...
Erdős Problems (#1077, https://www.erdosproblems.com/1077). Maintainer status: DISPROVED (LEAN). Formalized in Lean (google-deepmind/formal-conjectures, ErdosProblems.1077).
3
solved
Paul Erdős
null
3
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 3, "name": "graph_theory", "display_name": "Graph Theory", "description": "Problems involving graphs, networks, and their properties.", "slug": "graph-theory", "order_index": 3, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1077", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "disproved (Lean)" }
null
null
null
null
[ "erdos-problems", "graph-theory" ]
null
null
null
null
https://www.erdosproblems.com/1077
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,155
EP-1078
Erdős Problem #1078: If $G$ has minimum degree $\geq (r-\frac{3}{2}-o(1))n$ then $G$ must contain a $K_r$
Let $G$ be an $r$-partite graph with $n$ vertices in each part. If $G$ has minimum degree $\geq (r-\frac{3}{2}-o(1))n$ then $G$ must contain a $K_r$.
Erdős Problems (#1078, https://www.erdosproblems.com/1078). Maintainer status: PROVED.
3
solved
Paul Erdős
null
3
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 3, "name": "graph_theory", "display_name": "Graph Theory", "description": "Problems involving graphs, networks, and their properties.", "slug": "graph-theory", "order_index": 3, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1078", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "proved" }
null
null
null
null
[ "erdos-problems", "graph-theory" ]
null
null
null
null
https://www.erdosproblems.com/1078
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,156
EP-1079
Erdős Problem #1079: Graph Theory, Turan Number
Let $r\geq 4$. If $G$ is a graph on $n$ vertices with at least $\mathrm{ex}(n;K_r)$ edges then must $G$ contain a vertex with degree $d\gg_r n$ whose neighbourhood contains at least $\mathrm{ex}(d;K_{r-1})$ edges?
Erdős Problems (#1079, https://www.erdosproblems.com/1079). Maintainer status: SOLVED. Formalized in Lean (google-deepmind/formal-conjectures, ErdosProblems.1079).
3
solved
Paul Erdős
null
3
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 3, "name": "graph_theory", "display_name": "Graph Theory", "description": "Problems involving graphs, networks, and their properties.", "slug": "graph-theory", "order_index": 3, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1079", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "solved" }
null
null
null
null
[ "erdos-problems", "graph-theory", "turan-number" ]
null
null
null
null
https://www.erdosproblems.com/1079
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,157
EP-1080
Erdős Problem #1080: Graph Theory
Let $G$ be a bipartite graph on $n$ vertices such that one part has $\lfloor n^{2/3}\rfloor$ vertices. Is there a constant $c>0$ such that if $G$ has at least $cn$ edges then $G$ must contain a $C_6$?
Erdős Problems (#1080, https://www.erdosproblems.com/1080). Maintainer status: DISPROVED (LEAN). Formalized in Lean (google-deepmind/formal-conjectures, ErdosProblems.1080).
3
solved
Paul Erdős
null
3
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 3, "name": "graph_theory", "display_name": "Graph Theory", "description": "Problems involving graphs, networks, and their properties.", "slug": "graph-theory", "order_index": 3, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1080", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "disproved (Lean)" }
null
null
null
null
[ "erdos-problems", "graph-theory" ]
null
null
null
null
https://www.erdosproblems.com/1080
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,158
EP-1081
Erdős Problem #1081: Number Theory, Powerful
Let $A(x)$ count the number of $n\leq x$ which are the sum of two squarefull numbers (a number $m$ is squarefull if $p\mid m$ implies $p^2\mid m$). Is it true that\[A(x) \sim c \frac{x}{\sqrt{\log x}}\]for some $c>0$?
Erdős Problems (#1081, https://www.erdosproblems.com/1081). Maintainer status: DISPROVED. OEIS: A076871, A076872.
3
solved
Paul Erdős
null
1
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 1, "name": "number_theory", "display_name": "Number Theory", "description": "Properties of integers, prime numbers, Diophantine equations.", "slug": "number-theory", "order_index": 1, "created_at": "2026-07-31T15:26:25.670Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1081", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "disproved" }
null
null
null
null
[ "erdos-problems", "number-theory", "powerful" ]
null
null
null
null
https://www.erdosproblems.com/1081
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,159
EP-1082
Erdős Problem #1082: Geometry, Distances
Let $A\subset \mathbb{R}^2$ be a set of $n$ points with no three on a line. Does $A$ determine at least $\lfloor n/2\rfloor$ distinct distances? In fact, must there exist a single point from which there are at least $\lfloor n/2\rfloor$ distinct distances?
Erdős Problems (#1082, https://www.erdosproblems.com/1082). Maintainer status: FALSIFIABLE. Formalized in Lean (google-deepmind/formal-conjectures, ErdosProblems.1082).
3
open
Paul Erdős
null
6
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 6, "name": "geometry", "display_name": "Geometry", "description": "Euclidean and non-Euclidean geometry, geometric structures.", "slug": "geometry", "order_index": 6, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1082", "checked_at": "2026-10-16", "kind": "open", "evidence": "maintained_source", "maintainer_status": "falsifiable" }
null
null
null
null
[ "erdos-problems", "geometry", "distances" ]
null
null
null
null
https://www.erdosproblems.com/1082
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,160
EP-1090
Erdős Problem #1090: Geometry, Ramsey Theory
Let $k\geq 3$. Does there exist a finite set $A\subset \mathbb{R}^2$ such that, in any $2$-colouring of $A$, there exists a line which contains at least $k$ points from $A$, and all the points of $A$ on the line have the same colour?
Erdős Problems (#1090, https://www.erdosproblems.com/1090). Maintainer status: PROVED (LEAN). Formalized in Lean (google-deepmind/formal-conjectures, ErdosProblems.1090).
3
solved
Paul Erdős
null
6
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 6, "name": "geometry", "display_name": "Geometry", "description": "Euclidean and non-Euclidean geometry, geometric structures.", "slug": "geometry", "order_index": 6, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1090", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "proved (Lean)" }
null
null
null
null
[ "erdos-problems", "geometry", "ramsey-theory" ]
null
null
null
null
https://www.erdosproblems.com/1090
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,161
EP-1098
Erdős Problem #1098: Group Theory
Let $G$ be a group and $\Gamma=\Gamma(G)$ be the non-commuting graph, with vertices the elements of $G$ and an edge between $g$ and $h$ if and only if $g$ and $h$ do not commute, $gh\neq hg$. If $\Gamma$ contains no infinite complete subgraph, then is there a finite bound on the size of complete subgraphs of $\Gamma$?
Erdős Problems (#1098, https://www.erdosproblems.com/1098). Maintainer status: PROVED (LEAN). Formalized in Lean (google-deepmind/formal-conjectures, ErdosProblems.1098).
3
solved
Paul Erdős
null
1
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 1, "name": "number_theory", "display_name": "Number Theory", "description": "Properties of integers, prime numbers, Diophantine equations.", "slug": "number-theory", "order_index": 1, "created_at": "2026-07-31T15:26:25.670Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1098", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "proved (Lean)" }
null
null
null
null
[ "erdos-problems", "group-theory" ]
null
null
null
null
https://www.erdosproblems.com/1098
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,162
EP-1099
Erdős Problem #1099: Number Theory, Divisors
Let $1=d_1<\cdots<d_{\tau(n)}=n$ be the divisors of $n$, and for $\alpha>1$ let\[h_\alpha(n) = \sum_i \left( \frac{d_{i+1}}{d_i}-1\right)^\alpha.\]Is it true that\[\liminf_{n\to \infty}h_\alpha(n) \ll_\alpha 1?\]
Erdős Problems (#1099, https://www.erdosproblems.com/1099). Maintainer status: PROVED. Formalized in Lean (google-deepmind/formal-conjectures, ErdosProblems.1099).
3
solved
Paul Erdős
null
1
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 1, "name": "number_theory", "display_name": "Number Theory", "description": "Properties of integers, prime numbers, Diophantine equations.", "slug": "number-theory", "order_index": 1, "created_at": "2026-07-31T15:26:25.670Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1099", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "proved" }
null
null
null
null
[ "erdos-problems", "number-theory", "divisors" ]
null
null
null
null
https://www.erdosproblems.com/1099
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,163
EP-1102
Erdős Problem #1102: Number Theory
We say that $A\subseteq \mathbb{N}$ has property $P$ if, for all $n\geq 1$, there are only finitely many $a\in A$ such that $n+a$ is squarefree. We say that $A$ has property $Q$ if there are infinitely many $n$ such that $n+a$ is squarefree for all $a<n$. How fast must sequences $A=\{a_1<a_2<\cdots\}$ with properties...
Erdős Problems (#1102, https://www.erdosproblems.com/1102). Maintainer status: SOLVED (LEAN). Formalized in Lean (google-deepmind/formal-conjectures, ErdosProblems.1102).
3
solved
Paul Erdős
null
1
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 1, "name": "number_theory", "display_name": "Number Theory", "description": "Properties of integers, prime numbers, Diophantine equations.", "slug": "number-theory", "order_index": 1, "created_at": "2026-07-31T15:26:25.670Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1102", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "solved (Lean)" }
null
null
null
null
[ "erdos-problems", "number-theory" ]
null
null
null
null
https://www.erdosproblems.com/1102
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,164
EP-1114
Erdős Problem #1114:
Let $f(x)\in \mathbb{R}[x]$ be a polynomial of degree $n$ whose roots $\{a_0<\cdots<a_n\}$ are all real and form an arithmetic progression. The differences between consecutive zeros of $f'(x)$, beginning from the midpoint of $(a_0,a_m)$ towards the endpoints, are monotonically increasing.
Erdős Problems (#1114, https://www.erdosproblems.com/1114). Maintainer status: PROVED.
3
solved
Paul Erdős
null
8
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 8, "name": "analysis", "display_name": "Analysis", "description": "Limits, continuity, calculus, and function theory.", "slug": "analysis", "order_index": 8, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1114", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "proved" }
null
null
null
null
[ "erdos-problems", "analysis", "polynomials" ]
null
null
null
null
https://www.erdosproblems.com/1114
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,165
EP-1115
Erdős Problem #1115: Analysis
Let $f(z)$ be an entire function of finite order, and let $\Gamma$ be a rectifiable path on which $f(z)\to \infty$. Let $\ell(r)$ be the length of $\Gamma$ in the disc $\lvert z\rvert<r$. Find a path for which $\ell(r)$ grows as slowly as possible, and estimate $\ell(r)$ in terms of $M(r)=\max_{\lvert z\rvert=r}\lvert...
Erdős Problems (#1115, https://www.erdosproblems.com/1115). Maintainer status: SOLVED.
3
solved
Paul Erdős
null
8
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 8, "name": "analysis", "display_name": "Analysis", "description": "Limits, continuity, calculus, and function theory.", "slug": "analysis", "order_index": 8, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1115", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "solved" }
null
null
null
null
[ "erdos-problems", "analysis" ]
null
null
null
null
https://www.erdosproblems.com/1115
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,166
EP-1116
Erdős Problem #1116: Analysis
For a meromorphic function $f$ let $n(r,a)$ count the number of roots of $f(z)=a$ in the disc $\lvert z\rvert <r$. Does there exist a meromorphic (or entire) $f$ such that for every $a\neq b$\[\limsup_{r\to \infty}\frac{n(r,a)}{n(r,b)}=\infty?\]
Erdős Problems (#1116, https://www.erdosproblems.com/1116). Maintainer status: SOLVED.
3
solved
Paul Erdős
null
8
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 8, "name": "analysis", "display_name": "Analysis", "description": "Limits, continuity, calculus, and function theory.", "slug": "analysis", "order_index": 8, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1116", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "solved" }
null
null
null
null
[ "erdos-problems", "analysis" ]
null
null
null
null
https://www.erdosproblems.com/1116
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,167
EP-1118
Erdős Problem #1118: for some $c$, the set $E(c)=\{ z: \lvert f(z)\rvert >c\}$ has finite measure
Let $f(z)$ be a non-constant entire function such that, for some $c$, the set $E(c)=\{ z: \lvert f(z)\rvert >c\}$ has finite measure. What is the minimum growth rate of $f(z)$? If $E(c)$ has finite measure then must there exist $c'<c$ such that $E(c')$ has finite measure?
Erdős Problems (#1118, https://www.erdosproblems.com/1118). Maintainer status: SOLVED.
3
solved
Paul Erdős
null
8
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 8, "name": "analysis", "display_name": "Analysis", "description": "Limits, continuity, calculus, and function theory.", "slug": "analysis", "order_index": 8, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1118", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "solved" }
null
null
null
null
[ "erdos-problems", "analysis" ]
null
null
null
null
https://www.erdosproblems.com/1118
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,168
EP-1119
Erdős Problem #1119: Analysis, Set Theory
Let $\mathfrak{m}$ be an infinite cardinal with $\aleph_0<\mathfrak{m}<\mathfrak{c}=2^{\aleph_0}$. Let $\{f_\alpha\}$ be a family of entire functions such that, for every $z_0\in \mathbb{C}$, there are at most $\mathfrak{m}$ distinct values of $f_\alpha(z_0)$. Must $\{f_\alpha\}$ have cardinality at most $\mathfrak{m}$...
Erdős Problems (#1119, https://www.erdosproblems.com/1119). Maintainer status: INDEPENDENT. Formalized in Lean (google-deepmind/formal-conjectures, ErdosProblems.1119).
3
solved
Paul Erdős
null
8
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 8, "name": "analysis", "display_name": "Analysis", "description": "Limits, continuity, calculus, and function theory.", "slug": "analysis", "order_index": 8, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1119", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "independent" }
null
null
null
null
[ "erdos-problems", "analysis", "set-theory" ]
null
null
null
null
https://www.erdosproblems.com/1119
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,169
EP-1121
Erdős Problem #1121: Geometry
If $C_1,\ldots,C_n$ are circles in $\mathbb{R}^2$ with radii $r_1,\ldots,r_n$ such that no line disjoint from all the circles divides them into two non-empty sets then the circles can be covered by a circle of radius $r=\sum r_i$.
Erdős Problems (#1121, https://www.erdosproblems.com/1121). Maintainer status: PROVED (LEAN). Formalized in Lean (google-deepmind/formal-conjectures, ErdosProblems.1121).
3
solved
Paul Erdős
null
6
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 6, "name": "geometry", "display_name": "Geometry", "description": "Euclidean and non-Euclidean geometry, geometric structures.", "slug": "geometry", "order_index": 6, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1121", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "proved (Lean)" }
null
null
null
null
[ "erdos-problems", "geometry" ]
null
null
null
null
https://www.erdosproblems.com/1121
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,170
EP-1123
Erdős Problem #1123: Algebra
Let $B_1$ be the Boolean algebra of sets of integers modulo sets of density $0$ (that is, in which two sets are equivalent if and only if they differ by a set of density $0$) and let $B_2$ be the Boolean algebra of sets modulo sets of logarithmic density $0$. Prove that $B_1$ and $B_2$ are not isomorphic.
Erdős Problems (#1123, https://www.erdosproblems.com/1123). Maintainer status: INDEPENDENT. Erdős prize: $100.
3
solved
Paul Erdős
null
1
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 1, "name": "number_theory", "display_name": "Number Theory", "description": "Properties of integers, prime numbers, Diophantine equations.", "slug": "number-theory", "order_index": 1, "created_at": "2026-07-31T15:26:25.670Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1123", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "independent" }
null
null
null
null
[ "erdos-problems", "algebra" ]
null
null
null
null
https://www.erdosproblems.com/1123
Erdős Problems (erdosproblems.com)
$100
[]
null
null
null
null
null
null
null
null
null
null
30,007,171
EP-1124
Erdős Problem #1124: Geometry
Can a square and a circle of the same area be decomposed into a finite number of congruent parts?
Erdős Problems (#1124, https://www.erdosproblems.com/1124). Maintainer status: PROVED.
3
solved
Paul Erdős
null
6
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 6, "name": "geometry", "display_name": "Geometry", "description": "Euclidean and non-Euclidean geometry, geometric structures.", "slug": "geometry", "order_index": 6, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1124", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "proved" }
null
null
null
null
[ "erdos-problems", "geometry" ]
null
null
null
null
https://www.erdosproblems.com/1124
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,172
EP-1125
Erdős Problem #1125: Must $f$ be monotonic?
Let $f:\mathbb{R}\to \mathbb{R}$ be such that\[2f(x) \leq f(x+h)+f(x+2h)\]for every $x\in \mathbb{R}$ and $h>0$. Must $f$ be monotonic?
Erdős Problems (#1125, https://www.erdosproblems.com/1125). Maintainer status: PROVED (LEAN). Formalized in Lean (google-deepmind/formal-conjectures, ErdosProblems.1125).
3
solved
Paul Erdős
null
8
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 8, "name": "analysis", "display_name": "Analysis", "description": "Limits, continuity, calculus, and function theory.", "slug": "analysis", "order_index": 8, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1125", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "proved (Lean)" }
null
null
null
null
[ "erdos-problems", "analysis" ]
null
null
null
null
https://www.erdosproblems.com/1125
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,173
EP-1126
Erdős Problem #1126: Analysis
If\[f(x+y)=f(x)+f(y)\]for almost all $x,y\in \mathbb{R}$ then there exists a function $g$ such that\[g(x+y)=g(x)+g(y)\]for all $x,y\in\mathbb{R}$ such that $f(x)=g(x)$ for almost all $x$.
Erdős Problems (#1126, https://www.erdosproblems.com/1126). Maintainer status: PROVED (LEAN). Formalized in Lean (google-deepmind/formal-conjectures, ErdosProblems.1126).
3
solved
Paul Erdős
null
8
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 8, "name": "analysis", "display_name": "Analysis", "description": "Limits, continuity, calculus, and function theory.", "slug": "analysis", "order_index": 8, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1126", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "proved (Lean)" }
null
null
null
null
[ "erdos-problems", "analysis" ]
null
null
null
null
https://www.erdosproblems.com/1126
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,174
EP-1127
Erdős Problem #1127: Geometry, Distances
Can $\mathbb{R}^n$ be decomposed into countably many sets, such that within each set all the pairwise distances are distinct?
Erdős Problems (#1127, https://www.erdosproblems.com/1127). Maintainer status: INDEPENDENT.
3
solved
Paul Erdős
null
6
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 6, "name": "geometry", "display_name": "Geometry", "description": "Euclidean and non-Euclidean geometry, geometric structures.", "slug": "geometry", "order_index": 6, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1127", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "independent" }
null
null
null
null
[ "erdos-problems", "geometry", "distances", "set-theory" ]
null
null
null
null
https://www.erdosproblems.com/1127
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,175
EP-1128
Erdős Problem #1128: Set Theory, Ramsey Theory
Let $A,B,C$ be three sets of cardinality $\aleph_1$. Is it true that, in any $2$-colouring of $A\times B\times C$, there must exist $A_1\subset A$, $B_1\subset B$, $C_1\subset C$, all of cardinality $\aleph_0$, such that $A_1\times B_1\times C_1$ is monochromatic?
Erdős Problems (#1128, https://www.erdosproblems.com/1128). Maintainer status: DISPROVED (LEAN). Erdős prize: $50. Formalized in Lean (google-deepmind/formal-conjectures, ErdosProblems.1128).
3
solved
Paul Erdős
null
10
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 10, "name": "set_theory", "display_name": "Set Theory", "description": "Foundations of mathematics, infinite sets, and cardinality.", "slug": "set-theory", "order_index": 10, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1128", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "disproved (Lean)" }
null
null
null
null
[ "erdos-problems", "set-theory", "ramsey-theory", "hypergraphs" ]
null
null
null
null
https://www.erdosproblems.com/1128
Erdős Problems (erdosproblems.com)
$50
[]
null
null
null
null
null
null
null
null
null
null
30,007,176
EP-1134
Erdős Problem #1134: \]\[x\mapsto 3x+1,\]and\[x\mapsto 6x+1.\]Does $A$ have positive lower density?
Let $A\subseteq \mathbb{N}$ be the smallest set which contains $1$ and is closed under the operations\[x\mapsto 2x+1,\]\[x\mapsto 3x+1,\]and\[x\mapsto 6x+1.\]Does $A$ have positive lower density?
Erdős Problems (#1134, https://www.erdosproblems.com/1134). Maintainer status: DISPROVED (LEAN). Erdős prize: £10. OEIS: A185661. Formalized in Lean (google-deepmind/formal-conjectures, ErdosProblems.1134).
3
solved
Paul Erdős
null
1
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 1, "name": "number_theory", "display_name": "Number Theory", "description": "Properties of integers, prime numbers, Diophantine equations.", "slug": "number-theory", "order_index": 1, "created_at": "2026-07-31T15:26:25.670Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1134", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "disproved (Lean)" }
null
null
null
null
[ "erdos-problems", "number-theory" ]
null
null
null
null
https://www.erdosproblems.com/1134
Erdős Problems (erdosproblems.com)
£10
[]
null
null
null
null
null
null
null
null
null
null
30,007,177
EP-1136
Erdős Problem #1136: Number Theory
Does there exist $A\subset \mathbb{N}$ with lower density $>1/3$ such that $a+b\neq 2^k$ for any $a,b\in A$ and $k\geq 0$?
Erdős Problems (#1136, https://www.erdosproblems.com/1136). Maintainer status: PROVED (LEAN). Formalized in Lean (google-deepmind/formal-conjectures, ErdosProblems.1136).
3
solved
Paul Erdős
null
1
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 1, "name": "number_theory", "display_name": "Number Theory", "description": "Properties of integers, prime numbers, Diophantine equations.", "slug": "number-theory", "order_index": 1, "created_at": "2026-07-31T15:26:25.670Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1136", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "proved (Lean)" }
null
null
null
null
[ "erdos-problems", "number-theory" ]
null
null
null
null
https://www.erdosproblems.com/1136
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,178
EP-1137
Erdős Problem #1137: Number Theory, Primes
Let $d_n=p_{n+1}-p_n$, where $p_n$ denotes the $n$th prime. Is it true that\[\frac{\max_{n<x}d_{n}d_{n-1}}{(\max_{n<x}d_n)^2}\to 0\]as $x\to \infty$?
Erdős Problems (#1137, https://www.erdosproblems.com/1137). Maintainer status: OPEN. OEIS: A083550, A005250. Formalized in Lean (google-deepmind/formal-conjectures, ErdosProblems.1137).
3
open
Paul Erdős
null
1
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 1, "name": "number_theory", "display_name": "Number Theory", "description": "Properties of integers, prime numbers, Diophantine equations.", "slug": "number-theory", "order_index": 1, "created_at": "2026-07-31T15:26:25.670Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1137", "checked_at": "2026-10-16", "kind": "open", "evidence": "maintained_source", "maintainer_status": "open" }
null
null
null
null
[ "erdos-problems", "number-theory", "primes" ]
null
null
null
null
https://www.erdosproblems.com/1137
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,179
EP-1138
Erdős Problem #1138: Number Theory, Primes
Let $x/2<y<x$ and $C>1$. If $d=\max_{p_n<x} (p_{n+1}-p_n)$, where $p_n$ denotes the $n$th prime, then is it true that\[\pi(y+Cd)-\pi(y)\sim\frac{Cd}{\log y}?\]
Erdős Problems (#1138, https://www.erdosproblems.com/1138). Maintainer status: DISPROVED (LEAN). Formalized in Lean (google-deepmind/formal-conjectures, ErdosProblems.1138).
3
solved
Paul Erdős
null
1
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 1, "name": "number_theory", "display_name": "Number Theory", "description": "Properties of integers, prime numbers, Diophantine equations.", "slug": "number-theory", "order_index": 1, "created_at": "2026-07-31T15:26:25.670Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1138", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "disproved (Lean)" }
null
null
null
null
[ "erdos-problems", "number-theory", "primes" ]
null
null
null
null
https://www.erdosproblems.com/1138
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,180
EP-1139
Erdős Problem #1139: Is it true that\[\limsup \frac{u_{k+1}-u_k}{\log k}=\infty?\]
Let $1\leq u_1<u_2<\cdots$ be the sequence of integers with at most $2$ prime factors. Is it true that\[\limsup \frac{u_{k+1}-u_k}{\log k}=\infty?\]
Erdős Problems (#1139, https://www.erdosproblems.com/1139). Maintainer status: OPEN. OEIS: A037143, A101041. Formalized in Lean (google-deepmind/formal-conjectures, ErdosProblems.1139).
3
open
Paul Erdős
null
1
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 1, "name": "number_theory", "display_name": "Number Theory", "description": "Properties of integers, prime numbers, Diophantine equations.", "slug": "number-theory", "order_index": 1, "created_at": "2026-07-31T15:26:25.670Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1139", "checked_at": "2026-10-16", "kind": "open", "evidence": "maintained_source", "maintainer_status": "open" }
null
null
null
null
[ "erdos-problems", "number-theory", "primes" ]
null
null
null
null
https://www.erdosproblems.com/1139
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,181
EP-1140
Erdős Problem #1140: Number Theory
Do there exist infinitely many $n$ such that $n-2x^2$ is prime for all $x$ with $2x^2<n$?
Erdős Problems (#1140, https://www.erdosproblems.com/1140). Maintainer status: DISPROVED. OEIS: A240842.
3
solved
Paul Erdős
null
1
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 1, "name": "number_theory", "display_name": "Number Theory", "description": "Properties of integers, prime numbers, Diophantine equations.", "slug": "number-theory", "order_index": 1, "created_at": "2026-07-31T15:26:25.670Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1140", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "disproved" }
null
null
null
null
[ "erdos-problems", "number-theory" ]
null
null
null
null
https://www.erdosproblems.com/1140
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,182
EP-1141
Erdős Problem #1141: Number Theory, Primes
Are there infinitely many $n$ such that $n-k^2$ is prime for all $k$ with $(n,k)=1$ and $k^2<n$?
Erdős Problems (#1141, https://www.erdosproblems.com/1141). Maintainer status: DISPROVED (LEAN). OEIS: A214583. Formalized in Lean (google-deepmind/formal-conjectures, ErdosProblems.1141).
3
solved
Paul Erdős
null
1
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 1, "name": "number_theory", "display_name": "Number Theory", "description": "Properties of integers, prime numbers, Diophantine equations.", "slug": "number-theory", "order_index": 1, "created_at": "2026-07-31T15:26:25.670Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1141", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "disproved (Lean)" }
null
null
null
null
[ "erdos-problems", "number-theory", "primes" ]
null
null
null
null
https://www.erdosproblems.com/1141
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,183
EP-1142
Erdős Problem #1142: Number Theory, Primes
Are there infinitely many $n$ (or any $n>105$) such that $n-2^k$ is prime for all $1<2^k<n$?
Erdős Problems (#1142, https://www.erdosproblems.com/1142). Maintainer status: OPEN. OEIS: A039669. Formalized in Lean (google-deepmind/formal-conjectures, ErdosProblems.1142).
3
open
Paul Erdős
null
1
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 1, "name": "number_theory", "display_name": "Number Theory", "description": "Properties of integers, prime numbers, Diophantine equations.", "slug": "number-theory", "order_index": 1, "created_at": "2026-07-31T15:26:25.670Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
[ "GUY-A19a" ]
{ "source_url": "https://www.erdosproblems.com/1142", "checked_at": "2026-10-16", "kind": "open", "evidence": "maintained_source", "maintainer_status": "open" }
null
null
null
null
[ "erdos-problems", "number-theory", "primes" ]
null
null
null
null
https://www.erdosproblems.com/1142
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,184
EP-1143
Erdős Problem #1143: Number Theory, Primes
Let $p_1<\cdots<p_u$ be primes and let $k\geq 1$. Let $F_k(p_1,\ldots,p_u)$ be such that every interval of $k$ positive integers contains at least $F_k(p_1,\ldots,p_u)$ multiples of at least one of the $p_i$. Estimate $F_k(p_1,\ldots,p_u)$, particularly in the range $k=\alpha p_u$ for constant $\alpha>2$.
Erdős Problems (#1143, https://www.erdosproblems.com/1143). Maintainer status: OPEN.
3
open
Paul Erdős
null
1
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 1, "name": "number_theory", "display_name": "Number Theory", "description": "Properties of integers, prime numbers, Diophantine equations.", "slug": "number-theory", "order_index": 1, "created_at": "2026-07-31T15:26:25.670Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1143", "checked_at": "2026-10-16", "kind": "open", "evidence": "maintained_source", "maintainer_status": "open" }
null
null
null
null
[ "erdos-problems", "number-theory", "primes" ]
null
null
null
null
https://www.erdosproblems.com/1143
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,185
EP-1144
Erdős Problem #1144: Number Theory, Probability
Let $f$ be a random completely multiplicative function, where for each prime $p$ we independently choose $f(p)\in \{-1,1\}$ uniformly at random. Is it true that\[\limsup_{N\to \infty}\frac{\sum_{m\leq N}f(m)}{\sqrt{N}}=\infty\]with probability $1$?
Erdős Problems (#1144, https://www.erdosproblems.com/1144). Maintainer status: OPEN.
3
open
Paul Erdős
null
1
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 1, "name": "number_theory", "display_name": "Number Theory", "description": "Properties of integers, prime numbers, Diophantine equations.", "slug": "number-theory", "order_index": 1, "created_at": "2026-07-31T15:26:25.670Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1144", "checked_at": "2026-10-16", "kind": "open", "evidence": "maintained_source", "maintainer_status": "open" }
null
null
null
null
[ "erdos-problems", "number-theory", "probability" ]
null
null
null
null
https://www.erdosproblems.com/1144
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,186
EP-1145
Erdős Problem #1145: and $B=\{1\leq b_1<b_2<\cdots\}$ be sets of integers with $a_n/b_n\to 1$
Let $A=\{1\leq a_1<a_2<\cdots\}$ and $B=\{1\leq b_1<b_2<\cdots\}$ be sets of integers with $a_n/b_n\to 1$. If $A+B$ contains all sufficiently large positive integers then is it true that $\limsup 1_A\ast 1_B(n)=\infty$?
Erdős Problems (#1145, https://www.erdosproblems.com/1145). Maintainer status: OPEN. Formalized in Lean (google-deepmind/formal-conjectures, ErdosProblems.1145).
3
open
Paul Erdős
null
2
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 2, "name": "combinatorics", "display_name": "Combinatorics", "description": "Counting problems, graph theory, discrete structures.", "slug": "combinatorics", "order_index": 2, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1145", "checked_at": "2026-10-16", "kind": "open", "evidence": "maintained_source", "maintainer_status": "open" }
null
null
null
null
[ "erdos-problems", "additive-combinatorics", "additive-basis" ]
null
null
null
null
https://www.erdosproblems.com/1145
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,187
EP-1146
Erdős Problem #1146: Number Theory
We say that $A\subset \mathbb{N}$ is an essential component if $d_s(A+B)>d_s(B)$ for every $B\subset \mathbb{N}$ with $0<d_s(B)<1$ where $d_s$ is the Schnirelmann density. Is $B=\{2^m3^n: m,n\geq 0\}$ an essential component?
Erdős Problems (#1146, https://www.erdosproblems.com/1146). Maintainer status: OPEN. Formalized in Lean (google-deepmind/formal-conjectures, ErdosProblems.1146).
3
open
Paul Erdős
null
1
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 1, "name": "number_theory", "display_name": "Number Theory", "description": "Properties of integers, prime numbers, Diophantine equations.", "slug": "number-theory", "order_index": 1, "created_at": "2026-07-31T15:26:25.670Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1146", "checked_at": "2026-10-16", "kind": "open", "evidence": "maintained_source", "maintainer_status": "open" }
null
null
null
null
[ "erdos-problems", "number-theory" ]
null
null
null
null
https://www.erdosproblems.com/1146
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,188
EP-1147
Erdős Problem #1147: Irrational, Additive Basis
Let $\alpha>0$ be an irrational number. Is the set\[A=\left\{ n\geq 1: \| \alpha n^2\| < \frac{1}{\log n}\right\},\]where $\|\cdot\|$ denotes the distance to the nearest integer, an additive basis of order $2$?
Erdős Problems (#1147, https://www.erdosproblems.com/1147). Maintainer status: DISPROVED (LEAN). Formalized in Lean (google-deepmind/formal-conjectures, ErdosProblems.1147).
3
solved
Paul Erdős
null
1
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 1, "name": "number_theory", "display_name": "Number Theory", "description": "Properties of integers, prime numbers, Diophantine equations.", "slug": "number-theory", "order_index": 1, "created_at": "2026-07-31T15:26:25.670Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1147", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "disproved (Lean)" }
null
null
null
null
[ "erdos-problems", "irrational", "additive-basis" ]
null
null
null
null
https://www.erdosproblems.com/1147
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,189
EP-1148
Erdős Problem #1148: Number Theory
Can every large integer $n$ be written as $n=x^2+y^2-z^2$ with $\max(x^2,y^2,z^2)\leq n$?
Erdős Problems (#1148, https://www.erdosproblems.com/1148). Maintainer status: PROVED (LEAN). OEIS: A390380, A393168. Formalized in Lean (google-deepmind/formal-conjectures, ErdosProblems.1148).
3
solved
Paul Erdős
null
1
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 1, "name": "number_theory", "display_name": "Number Theory", "description": "Properties of integers, prime numbers, Diophantine equations.", "slug": "number-theory", "order_index": 1, "created_at": "2026-07-31T15:26:25.670Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1148", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "proved (Lean)" }
null
null
null
null
[ "erdos-problems", "number-theory" ]
null
null
null
null
https://www.erdosproblems.com/1148
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,190
EP-1149
Erdős Problem #1149: Number Theory
Let $\alpha>0$ be a real number, not an integer. The density of integers $n\geq 1$ for which $(n,\lfloor n^\alpha\rfloor)=1$ is $6/\pi^2$.
Erdős Problems (#1149, https://www.erdosproblems.com/1149). Maintainer status: PROVED. Formalized in Lean (google-deepmind/formal-conjectures, ErdosProblems.1149).
3
solved
Paul Erdős
null
1
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 1, "name": "number_theory", "display_name": "Number Theory", "description": "Properties of integers, prime numbers, Diophantine equations.", "slug": "number-theory", "order_index": 1, "created_at": "2026-07-31T15:26:25.670Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1149", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "proved" }
null
null
null
null
[ "erdos-problems", "number-theory" ]
null
null
null
null
https://www.erdosproblems.com/1149
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,191
EP-1150
Erdős Problem #1150: Analysis, Polynomials
Does there exist a constant $c>0$ such that, for all large $n$ and all polynomials $P$ of degree $n$ with coefficients $\pm 1$,\[\max_{\lvert z\rvert=1}\lvert P(z)\rvert > (1+c)\sqrt{n}?\]
Erdős Problems (#1150, https://www.erdosproblems.com/1150). Maintainer status: OPEN. Formalized in Lean (google-deepmind/formal-conjectures, ErdosProblems.1150).
3
open
Paul Erdős
null
8
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 8, "name": "analysis", "display_name": "Analysis", "description": "Limits, continuity, calculus, and function theory.", "slug": "analysis", "order_index": 8, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1150", "checked_at": "2026-10-16", "kind": "open", "evidence": "maintained_source", "maintainer_status": "open" }
null
null
null
null
[ "erdos-problems", "analysis", "polynomials" ]
null
null
null
null
https://www.erdosproblems.com/1150
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,192
EP-1151
Erdős Problem #1151: Analysis, Polynomials
Given $a_1,\ldots,a_n\in [-1,1]$ let\[\mathcal{L}^nf(x) = \sum_{1\leq i\leq n}f(a_i)\ell_i(x)\]be the unique polynomial of degree $n-1$ which agrees with $f$ on $a_i$ for $1\leq i\leq n$ (that is, the Lagrange interpolation polynomial). Let $a_i$ be the set of Chebyshev nodes. Prove that, for any closed $A\subseteq [-...
Erdős Problems (#1151, https://www.erdosproblems.com/1151). Maintainer status: OPEN.
3
open
Paul Erdős
null
8
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 8, "name": "analysis", "display_name": "Analysis", "description": "Limits, continuity, calculus, and function theory.", "slug": "analysis", "order_index": 8, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1151", "checked_at": "2026-10-16", "kind": "open", "evidence": "maintained_source", "maintainer_status": "open" }
null
null
null
null
[ "erdos-problems", "analysis", "polynomials" ]
null
null
null
null
https://www.erdosproblems.com/1151
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,193
EP-1152
Erdős Problem #1152: Analysis, Polynomials
For $n\geq 1$ fix some sequence of $n$ distinct numbers $x_{1n},\ldots,x_{nn}\in [-1,1]$. Let $\epsilon=\epsilon(n)\to 0$. Does there always exist a continuous function $f:[-1,1]\to \mathbb{R}$ such that if $p_n$ is a sequence of polynomials, with degrees $\deg p_n<(1+\epsilon(n))n$, such that $p_n(x_{kn})=f(x_{kn})$ ...
Erdős Problems (#1152, https://www.erdosproblems.com/1152). Maintainer status: OPEN.
3
open
Paul Erdős
null
8
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 8, "name": "analysis", "display_name": "Analysis", "description": "Limits, continuity, calculus, and function theory.", "slug": "analysis", "order_index": 8, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1152", "checked_at": "2026-10-16", "kind": "open", "evidence": "maintained_source", "maintainer_status": "open" }
null
null
null
null
[ "erdos-problems", "analysis", "polynomials" ]
null
null
null
null
https://www.erdosproblems.com/1152
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,194
EP-1153
Erdős Problem #1153: Analysis, Polynomials
For $x_1,\ldots,x_n\in [-1,1]$ let\[l_k(x)=\frac{\prod_{i\neq k}(x-x_i)}{\prod_{i\neq k}(x_k-x_i)},\]which are such that $l_k(x_k)=1$ and $l_k(x_i)=0$ for $i\neq k$. Let\[\lambda(x)=\sum_k \lvert l_k(x)\rvert.\]Is it true that, for any fixed $-1\leq a< b\leq 1$,\[\max_{x\in [a,b]}\lambda(x)> \left(\frac{2}{\pi}-o(1)\r...
Erdős Problems (#1153, https://www.erdosproblems.com/1153). Maintainer status: PROVED.
3
solved
Paul Erdős
null
8
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 8, "name": "analysis", "display_name": "Analysis", "description": "Limits, continuity, calculus, and function theory.", "slug": "analysis", "order_index": 8, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1153", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "proved" }
null
null
null
null
[ "erdos-problems", "analysis", "polynomials" ]
null
null
null
null
https://www.erdosproblems.com/1153
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,195
EP-1154
Erdős Problem #1154: Analysis
Does there exist, for every $\alpha \in [0,1]$, a ring or field in $\mathbb{R}$ with Hausdorff dimension $\alpha$?
Erdős Problems (#1154, https://www.erdosproblems.com/1154). Maintainer status: NOT DISPROVABLE. Formalized in Lean (google-deepmind/formal-conjectures, ErdosProblems.1154).
3
partially_solved
Paul Erdős
null
8
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 8, "name": "analysis", "display_name": "Analysis", "description": "Limits, continuity, calculus, and function theory.", "slug": "analysis", "order_index": 8, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1154", "checked_at": "2026-10-16", "kind": "partial", "evidence": "maintained_source", "maintainer_status": "not disprovable" }
null
null
null
null
[ "erdos-problems", "analysis" ]
null
null
null
null
https://www.erdosproblems.com/1154
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,196
EP-1155
Erdős Problem #1155: Graph Theory
Construct a random graph on $n$ vertices in the following way: begin with the complete graph $K_n$. At each stage, choose uniformly a random triangle in the graph and delete all the edges of this triangle. Repeat until the graph is triangle-free. Describe the typical parameters and structure of such a graph. In partic...
Erdős Problems (#1155, https://www.erdosproblems.com/1155). Maintainer status: OPEN.
3
open
Paul Erdős
null
3
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 3, "name": "graph_theory", "display_name": "Graph Theory", "description": "Problems involving graphs, networks, and their properties.", "slug": "graph-theory", "order_index": 3, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1155", "checked_at": "2026-10-16", "kind": "open", "evidence": "maintained_source", "maintainer_status": "open" }
null
null
null
null
[ "erdos-problems", "graph-theory" ]
null
null
null
null
https://www.erdosproblems.com/1155
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,197
EP-1156
Erdős Problem #1156: in which every edge is included independently with probability $1/2$
Let $G$ be a random graph on $n$ vertices, in which every edge is included independently with probability $1/2$. Is there some constant $C$ such that that chromatic number $\chi(G)$ is, almost surely, concentrated on at most $C$ values? Is it true that, if $\omega(n)\to \infty$ sufficiently slowly, then for every fun...
Erdős Problems (#1156, https://www.erdosproblems.com/1156). Maintainer status: OPEN.
3
open
Paul Erdős
null
3
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 3, "name": "graph_theory", "display_name": "Graph Theory", "description": "Problems involving graphs, networks, and their properties.", "slug": "graph-theory", "order_index": 3, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1156", "checked_at": "2026-10-16", "kind": "open", "evidence": "maintained_source", "maintainer_status": "open" }
null
null
null
null
[ "erdos-problems", "graph-theory", "chromatic-number" ]
null
null
null
null
https://www.erdosproblems.com/1156
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,198
EP-1157
Erdős Problem #1157: Hypergraphs, Turan Number
Let $t,k,r\geq 2$. Let $\mathcal{F}$ be the family of all $r$-uniform hypergraphs with $k$ vertices and $s$ edges. Determine\[\mathrm{ex}_r(n,\mathcal{F}).\]
Erdős Problems (#1157, https://www.erdosproblems.com/1157). Maintainer status: OPEN. Formalized in Lean (google-deepmind/formal-conjectures, ErdosProblems.1157).
3
open
Paul Erdős
null
2
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 2, "name": "combinatorics", "display_name": "Combinatorics", "description": "Counting problems, graph theory, discrete structures.", "slug": "combinatorics", "order_index": 2, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1157", "checked_at": "2026-10-16", "kind": "open", "evidence": "maintained_source", "maintainer_status": "open" }
null
null
null
null
[ "erdos-problems", "hypergraphs", "turan-number" ]
null
null
null
null
https://www.erdosproblems.com/1157
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,199
EP-1158
Erdős Problem #1158:
Let $K_{t}(r)$ be the complete $t$-partite $t$-uniform hypergraph with $r$ vertices in each class. Is it true that\[\mathrm{ex}_t(n,K_t(r)) \geq n^{t-r^{1-t}-o(1)}\]for all $t,r$?
Erdős Problems (#1158, https://www.erdosproblems.com/1158). Maintainer status: OPEN. Formalized in Lean (google-deepmind/formal-conjectures, ErdosProblems.1158).
3
open
Paul Erdős
null
2
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 2, "name": "combinatorics", "display_name": "Combinatorics", "description": "Counting problems, graph theory, discrete structures.", "slug": "combinatorics", "order_index": 2, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1158", "checked_at": "2026-10-16", "kind": "open", "evidence": "maintained_source", "maintainer_status": "open" }
null
null
null
null
[ "erdos-problems", "hypergraphs", "turan-number" ]
null
null
null
null
https://www.erdosproblems.com/1158
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,200
EP-1159
Erdős Problem #1159: Determine whether there exists a constant $C>1$ such that the following holds
Determine whether there exists a constant $C>1$ such that the following holds. Let $P$ be a finite projective plane. Must there exist a set of points $S$ such that $1\leq \lvert S\cap \ell\rvert \leq C$ for all lines $\ell$?
Erdős Problems (#1159, https://www.erdosproblems.com/1159). Maintainer status: OPEN. Formalized in Lean (google-deepmind/formal-conjectures, ErdosProblems.1159).
3
open
Paul Erdős
null
2
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 2, "name": "combinatorics", "display_name": "Combinatorics", "description": "Counting problems, graph theory, discrete structures.", "slug": "combinatorics", "order_index": 2, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1159", "checked_at": "2026-10-16", "kind": "open", "evidence": "maintained_source", "maintainer_status": "open" }
null
null
null
null
[ "erdos-problems", "combinatorics" ]
null
null
null
null
https://www.erdosproblems.com/1159
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,201
EP-1160
Erdős Problem #1160: denote the number of groups of order $n$. If $n\leq 2^m$ then $g(n)\leq g(2^m)$
Let $g(n)$ denote the number of groups of order $n$. If $n\leq 2^m$ then $g(n)\leq g(2^m)$.
Erdős Problems (#1160, https://www.erdosproblems.com/1160). Maintainer status: OPEN. OEIS: A000001.
3
open
Paul Erdős
null
1
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 1, "name": "number_theory", "display_name": "Number Theory", "description": "Properties of integers, prime numbers, Diophantine equations.", "slug": "number-theory", "order_index": 1, "created_at": "2026-07-31T15:26:25.670Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1160", "checked_at": "2026-10-16", "kind": "open", "evidence": "maintained_source", "maintainer_status": "open" }
null
null
null
null
[ "erdos-problems", "group-theory" ]
null
null
null
null
https://www.erdosproblems.com/1160
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,202
EP-1161
Erdős Problem #1161: Group Theory
Let $f_k(n)$ count the number of elements of $S_n$ of order $k$. For which values of $k$ will $f_k(n)$ be maximal?
Erdős Problems (#1161, https://www.erdosproblems.com/1161). Maintainer status: SOLVED. OEIS: A057731.
3
solved
Paul Erdős
null
1
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 1, "name": "number_theory", "display_name": "Number Theory", "description": "Properties of integers, prime numbers, Diophantine equations.", "slug": "number-theory", "order_index": 1, "created_at": "2026-07-31T15:26:25.670Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1161", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "solved" }
null
null
null
null
[ "erdos-problems", "group-theory" ]
null
null
null
null
https://www.erdosproblems.com/1161
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,203
EP-1162
Erdős Problem #1162: Group Theory
Give an asymptotic formula for the number of subgroups of $S_n$. Is there a statistical theorem on their order?
Erdős Problems (#1162, https://www.erdosproblems.com/1162). Maintainer status: OPEN. OEIS: A005432.
3
open
Paul Erdős
null
1
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 1, "name": "number_theory", "display_name": "Number Theory", "description": "Properties of integers, prime numbers, Diophantine equations.", "slug": "number-theory", "order_index": 1, "created_at": "2026-07-31T15:26:25.670Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1162", "checked_at": "2026-10-16", "kind": "open", "evidence": "maintained_source", "maintainer_status": "open" }
null
null
null
null
[ "erdos-problems", "group-theory" ]
null
null
null
null
https://www.erdosproblems.com/1162
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,204
EP-1163
Erdős Problem #1163: Group Theory
Describe (by statistical means) the arithmetic structure of the orders of subgroups of $S_n$.
Erdős Problems (#1163, https://www.erdosproblems.com/1163). Maintainer status: OPEN. ambiguous statement
3
open
Paul Erdős
null
1
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 1, "name": "number_theory", "display_name": "Number Theory", "description": "Properties of integers, prime numbers, Diophantine equations.", "slug": "number-theory", "order_index": 1, "created_at": "2026-07-31T15:26:25.670Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1163", "checked_at": "2026-10-16", "kind": "open", "evidence": "maintained_source", "maintainer_status": "open" }
null
null
null
ambiguous statement
[ "erdos-problems", "group-theory" ]
null
null
null
null
https://www.erdosproblems.com/1163
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,205
EP-1164
Erdős Problem #1164:
Let $R_n$ be the maximal integer such that almost every random walk from the origin in $\mathbb{Z}^2$ visits every $x\in\mathbb{Z}^2$ with $\| x\|\leq R_n$ in at most $n$ steps. Is it true that\[\log R_n \asymp \sqrt{\log n}?\]
Erdős Problems (#1164, https://www.erdosproblems.com/1164). Maintainer status: PROVED.
3
solved
Paul Erdős
null
1
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 1, "name": "number_theory", "display_name": "Number Theory", "description": "Properties of integers, prime numbers, Diophantine equations.", "slug": "number-theory", "order_index": 1, "created_at": "2026-07-31T15:26:25.670Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1164", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "proved" }
null
null
null
null
[ "erdos-problems", "probability" ]
null
null
null
null
https://www.erdosproblems.com/1164
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,206
EP-1165
Erdős Problem #1165: Probability
Given a random walk $s_0,s_1,\ldots$ in $\mathbb{Z}^2$, starting at the origin, let $f_n(x)$ count the number of $0\leq k\leq n$ such that $s_k=x$. Let\[F(n)=\{ x: f_n(x) = \max_y f_n(y)\}\]be the set of 'favourite values'. Find\[\mathbb{P}(\lvert F(n)\rvert=r\textrm{ infinitely often})\]for $r\geq 3$.
Erdős Problems (#1165, https://www.erdosproblems.com/1165). Maintainer status: SOLVED.
3
solved
Paul Erdős
null
1
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 1, "name": "number_theory", "display_name": "Number Theory", "description": "Properties of integers, prime numbers, Diophantine equations.", "slug": "number-theory", "order_index": 1, "created_at": "2026-07-31T15:26:25.670Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1165", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "solved" }
null
null
null
null
[ "erdos-problems", "probability" ]
null
null
null
null
https://www.erdosproblems.com/1165
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,207
EP-1166
Erdős Problem #1166: Probability
Given a random walk $s_0,s_1,\ldots$ in $\mathbb{Z}^2$, starting at the origin, let $f_k(x)$ count the number of $0\leq l\leq k$ such that $s_l=x$. Let\[F(k)=\{ x: f_k(x) = \max_y f_k(y)\}\]be the set of 'favourite values'. Is it true that\[\left\lvert \bigcup_{k\leq n}F(k)\right\rvert \leq (\log n)^{O(1)}\]almost sur...
Erdős Problems (#1166, https://www.erdosproblems.com/1166). Maintainer status: PROVED.
3
solved
Paul Erdős
null
1
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 1, "name": "number_theory", "display_name": "Number Theory", "description": "Properties of integers, prime numbers, Diophantine equations.", "slug": "number-theory", "order_index": 1, "created_at": "2026-07-31T15:26:25.670Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1166", "checked_at": "2026-10-16", "kind": "resolution", "evidence": "maintained_source", "maintainer_status": "proved" }
null
null
null
null
[ "erdos-problems", "probability" ]
null
null
null
null
https://www.erdosproblems.com/1166
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,208
EP-1167
Erdős Problem #1167: Let $\kappa_\alpha$ be cardinals for all $\alpha<\gamma$
Let $r\geq 2$ be finite and $\lambda$ be an infinite cardinal. Let $\kappa_\alpha$ be cardinals for all $\alpha<\gamma$. Is it true that\[2^\lambda \to (\kappa_\alpha+1)_{\alpha<\gamma}^{r+1}\]implies\[\lambda \to (\kappa_\alpha)_{\alpha<\gamma}^{r}?\]Here $+$ means cardinal addition, so that $\kappa_\alpha+1=\kappa_\...
Erdős Problems (#1167, https://www.erdosproblems.com/1167). Maintainer status: OPEN. Formalized in Lean (google-deepmind/formal-conjectures, ErdosProblems.1167).
3
open
Paul Erdős
null
10
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 10, "name": "set_theory", "display_name": "Set Theory", "description": "Foundations of mathematics, infinite sets, and cardinality.", "slug": "set-theory", "order_index": 10, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1167", "checked_at": "2026-10-16", "kind": "open", "evidence": "maintained_source", "maintainer_status": "open" }
null
null
null
null
[ "erdos-problems", "set-theory", "ramsey-theory" ]
null
null
null
null
https://www.erdosproblems.com/1167
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,209
EP-1168
Erdős Problem #1168: Set Theory, Ramsey Theory
Prove that\[\aleph_{\omega+1}\not\to (\aleph_{\omega+1}, 3,\ldots,3)_{\aleph_0}^2\]without assuming the generalised continuum hypothesis.
Erdős Problems (#1168, https://www.erdosproblems.com/1168). Maintainer status: OPEN.
3
open
Paul Erdős
null
10
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 10, "name": "set_theory", "display_name": "Set Theory", "description": "Foundations of mathematics, infinite sets, and cardinality.", "slug": "set-theory", "order_index": 10, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1168", "checked_at": "2026-10-16", "kind": "open", "evidence": "maintained_source", "maintainer_status": "open" }
null
null
null
null
[ "erdos-problems", "set-theory", "ramsey-theory" ]
null
null
null
null
https://www.erdosproblems.com/1168
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,210
EP-1169
Erdős Problem #1169: Is it true that, for all finite $k<\omega$,\[\omega_1^2 \not\to (\omega_1^2, 3)^2?\]
Is it true that, for all finite $k<\omega$,\[\omega_1^2 \not\to (\omega_1^2, 3)^2?\]
Erdős Problems (#1169, https://www.erdosproblems.com/1169). Maintainer status: NOT DISPROVABLE.
3
partially_solved
Paul Erdős
null
10
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 10, "name": "set_theory", "display_name": "Set Theory", "description": "Foundations of mathematics, infinite sets, and cardinality.", "slug": "set-theory", "order_index": 10, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1169", "checked_at": "2026-10-16", "kind": "partial", "evidence": "maintained_source", "maintainer_status": "not disprovable" }
null
null
null
null
[ "erdos-problems", "set-theory", "ramsey-theory" ]
null
null
null
null
https://www.erdosproblems.com/1169
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,211
EP-1170
Erdős Problem #1170: Is it consistent that\[\omega_2\to (\alpha)_2^2\]for every $\alpha <\omega_2$?
Is it consistent that\[\omega_2\to (\alpha)_2^2\]for every $\alpha <\omega_2$?
Erdős Problems (#1170, https://www.erdosproblems.com/1170). Maintainer status: OPEN.
3
open
Paul Erdős
null
10
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 10, "name": "set_theory", "display_name": "Set Theory", "description": "Foundations of mathematics, infinite sets, and cardinality.", "slug": "set-theory", "order_index": 10, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1170", "checked_at": "2026-10-16", "kind": "open", "evidence": "maintained_source", "maintainer_status": "open" }
null
null
null
null
[ "erdos-problems", "set-theory", "ramsey-theory" ]
null
null
null
null
https://www.erdosproblems.com/1170
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,212
EP-1171
Erdős Problem #1171: Set Theory, Ramsey Theory
Is it true that, for all finite $k<\omega$,\[\omega_1^2\to (\omega_1\omega, 3,\ldots,3)_{k+1}^2?\]
Erdős Problems (#1171, https://www.erdosproblems.com/1171). Maintainer status: NOT DISPROVABLE.
3
partially_solved
Paul Erdős
null
10
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 10, "name": "set_theory", "display_name": "Set Theory", "description": "Foundations of mathematics, infinite sets, and cardinality.", "slug": "set-theory", "order_index": 10, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1171", "checked_at": "2026-10-16", "kind": "partial", "evidence": "maintained_source", "maintainer_status": "not disprovable" }
null
null
null
null
[ "erdos-problems", "set-theory", "ramsey-theory" ]
null
null
null
null
https://www.erdosproblems.com/1171
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,213
EP-1172
Erdős Problem #1172: Set Theory, Ramsey Theory
Establish whether the following are true assuming the generalised continuum hypothesis:\[\omega_3 \to (\omega_2,\omega_1+2)^2,\]\[\omega_3\to (\omega_2+\omega_1,\omega_2+\omega)^2,\]\[\omega_2\to (\omega_1^{\omega+2}+2, \omega_1+2)^2.\]Establish whether the following is consistent with the generalised continuum hypothe...
Erdős Problems (#1172, https://www.erdosproblems.com/1172). Maintainer status: OPEN.
3
open
Paul Erdős
null
10
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 10, "name": "set_theory", "display_name": "Set Theory", "description": "Foundations of mathematics, infinite sets, and cardinality.", "slug": "set-theory", "order_index": 10, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1172", "checked_at": "2026-10-16", "kind": "open", "evidence": "maintained_source", "maintainer_status": "open" }
null
null
null
null
[ "erdos-problems", "set-theory", "ramsey-theory" ]
null
null
null
null
https://www.erdosproblems.com/1172
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,214
EP-1173
Erdős Problem #1173: Set Theory, Combinatorics
Assume the generalised continuum hypothesis. Let\[f: \omega_{\omega+1}\to [\omega_{\omega+1}]^{\leq \aleph_\omega}\]be a set mapping such that\[\lvert f(\alpha)\cap f(\beta)\rvert <\aleph_\omega\]for all $\alpha\neq \beta$. Does there exist a free set of cardinality $\aleph_{\omega+1}$?
Erdős Problems (#1173, https://www.erdosproblems.com/1173). Maintainer status: OPEN.
3
open
Paul Erdős
null
10
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 10, "name": "set_theory", "display_name": "Set Theory", "description": "Foundations of mathematics, infinite sets, and cardinality.", "slug": "set-theory", "order_index": 10, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1173", "checked_at": "2026-10-16", "kind": "open", "evidence": "maintained_source", "maintainer_status": "open" }
null
null
null
null
[ "erdos-problems", "set-theory", "combinatorics" ]
null
null
null
null
https://www.erdosproblems.com/1173
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null
30,007,215
EP-1174
Erdős Problem #1174: Set Theory, Ramsey Theory
Does there exist a graph $G$ with no $K_4$ such that every edge colouring of $G$ with countably many colours contains a monochromatic $K_3$? Does there exist a graph $G$ with no $K_{\aleph_1}$ such that every edge colouring of $G$ with countably many colours contains a monochromatic $K_{\aleph_0}$?
Erdős Problems (#1174, https://www.erdosproblems.com/1174). Maintainer status: NOT DISPROVABLE.
3
partially_solved
Paul Erdős
null
10
8
0
0
2026-10-16T14:00:00
2026-10-16T14:00:00
true
{ "id": 10, "name": "set_theory", "display_name": "Set Theory", "description": "Foundations of mathematics, infinite sets, and cardinality.", "slug": "set-theory", "order_index": 10, "created_at": "2026-07-31T15:26:25.671Z" }
{ "id": 3, "level": 3, "name": "L3: Advanced", "description": "Difficult problems requiring specialized knowledge and sophisticated techniques.", "color_class": "text-yellow-600 bg-yellow-50 border-yellow-200" }
{ "id": 8, "name": "erdos_problems", "display_name": "Erdős Problems", "description": "A collection of open problems posed by Paul Erdős, one of the most prolific mathematicians of the 20th century. These problems span combinatorics, number theory, graph theory, and analysis.", "slug": "erdos-problems", "or...
null
{ "source_url": "https://www.erdosproblems.com/1174", "checked_at": "2026-10-16", "kind": "partial", "evidence": "maintained_source", "maintainer_status": "not disprovable" }
null
null
null
null
[ "erdos-problems", "set-theory", "ramsey-theory" ]
null
null
null
null
https://www.erdosproblems.com/1174
Erdős Problems (erdosproblems.com)
null
[]
null
null
null
null
null
null
null
null
null
null