AlexKontorovich/PrimeNumberTheoremAnd
Source indexedtheorem · leanprover/lean4:v4.32.0
CH2.Phi_circ.analyticAt_of_not_pole
PrimeNumberTheoremAnd.IEANTN.CH2.CH2_part1 · PrimeNumberTheoremAnd/IEANTN/CH2/CH2_part1.lean:2096 to 2104
Source documentation
Phi_circ is analytic whenever we are away from the poles.
Exact Lean statement
theorem Phi_circ.analyticAt_of_not_pole (ν ε : ℝ) (z : ℂ) (h_not_pole : ∀ n : ℤ, z ≠ n - I * ν / (2 * π)) :
AnalyticAt ℂ (Phi_circ ν ε) zComplete declaration
Lean source
Full Lean sourceLean 4
theorem Phi_circ.analyticAt_of_not_pole (ν ε : ℝ) (z : ℂ) (h_not_pole : ∀ n : ℤ, z ≠ n - I * ν / (2 * π)) : AnalyticAt ℂ (Phi_circ ν ε) z := by set w : ℂ := -2 * π * I * z + ν have h_an : AnalyticAt ℂ (fun s : ℂ ↦ coth (s / 2)) w := by have heq : (fun s : ℂ ↦ coth (s / 2)) =ᶠ[nhds w] (fun s ↦ Complex.cosh (s / 2) / Complex.sinh (s / 2)) := Filter.Eventually.of_forall (fun s ↦ by unfold coth; simp [Complex.tanh_eq_sinh_div_cosh]) apply (analyticAt_congr heq).mpr fun_prop (disch := exact sinh_ne_zero_of_not_pole h_not_pole) unfold Phi_circ; fun_prop (disch := exact [h_an.comp (by fun_prop), by simp [w]; fun_prop])