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Add lean source and binary files (part 40)
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import Mathlib.Order.Interval.Finset.Fin
import OAI.Combinatorics.BalancedRyser.Probability.ExposureSchedule
namespace OAI
namespace Balanced.ExposureInterleaving
theorem previous_card_eq_time {n m : ℕ} {γ : ℝ} (hγ : 0 < γ)
(t : Fin (n + m)) :
(previousD γ (timeEquiv hγ t)).card +
(previousC γ (timeEquiv hγ t)).card = t.val := by
classical
rw [← Finset.card_disjSum]
have heq : (previousD γ (timeEquiv hγ t)).disjSum
(previousC γ (timeEquiv hγ t)) =
(Finset.Iio t).map (timeEquiv hγ).toEmbedding := by
ext s
rcases s with i | j
· simp only [Finset.inl_mem_disjSum, mem_previousD_iff_time hγ, Finset.mem_map,
Finset.mem_Iio, Equiv.toEmbedding_apply]
constructor
· intro hi
exact ⟨deletionTime hγ i, hi, by simp [deletionTime]⟩
· rintro ⟨u, hu, he⟩
have h : u = deletionTime hγ i := by
apply (timeEquiv hγ).injective
simpa [deletionTime] using he
simpa [h] using hu
· simp only [Finset.inr_mem_disjSum, mem_previousC_iff_time hγ, Finset.mem_map,
Finset.mem_Iio, Equiv.toEmbedding_apply]
constructor
· intro hj
exact ⟨coverTime hγ j, hj, by simp [coverTime]⟩
· rintro ⟨u, hu, he⟩
have h : u = coverTime hγ j := by
apply (timeEquiv hγ).injective
simpa [coverTime] using he
simpa [h] using hu
rw [heq, Finset.card_map, Fin.card_Iio]
theorem remaining_card_eq_time {n m : ℕ} {γ : ℝ} (hγ : 0 < γ)
(t : Fin (n + m)) :
(remainingD γ (timeEquiv hγ t)).card +
(remainingC γ (timeEquiv hγ t)).card = n + m - t.val := by
have hD := previousD_add_remainingD γ (timeEquiv hγ t)
have hC := previousC_add_remainingC γ (timeEquiv hγ t)
have hT := previous_card_eq_time hγ t
omega
end Balanced.ExposureInterleaving
end OAI