diff --git a/LeanBlockCourse26/P06_Mathlib/S01_PrimeTheorem.lean b/LeanBlockCourse26/P06_Mathlib/S01_PrimeTheorem.lean index a55245e..89e392f 100644 --- a/LeanBlockCourse26/P06_Mathlib/S01_PrimeTheorem.lean +++ b/LeanBlockCourse26/P06_Mathlib/S01_PrimeTheorem.lean @@ -194,8 +194,21 @@ theorem infinitude_of_primes_tfae {ℵ₀} : [ tfae_have 3 → 4 := by sorry -- Alexandra tfae_have 5 → 4 := by sorry -- Sammy - - tfae_have 6 → 3 := by sorry -- Anna + + tfae_have 6 → 3 := by + intro h + rcases h with ⟨P, hP_inj, hP_prime⟩ + intro S + -- die Menge des Bilds von der inj. Fkt P ist unendlich + have hR : (Set.range P).Infinite := Set.infinite_range_of_injective hP_inj + -- ∃ p ∈ ℕ , p ∈ hR ∧ p ∉ S , weil S endl. hR unendlich + obtain ⟨p, hpR, hpS⟩ := Set.Infinite.exists_notMem_finset hR S + -- p ∈ hR -> ∃ k ∈ ℕ , p = P k + rcases hpR with ⟨k, rfl⟩ + -- p = P k ist eine Primzahl + have g : Nat.Prime (P k) := hP_prime k + use (P k) + tfae_have 6 → 1 := by sorry -- Alexander