AlexKontorovich/PrimeNumberTheoremAnd
Source indexedlemma · leanprover/lean4:v4.32.0
FKS2.tendsto_log_div_self_mul_integral_atTop_zero
PrimeNumberTheoremAnd.IEANTN.FKS2 · PrimeNumberTheoremAnd/IEANTN/FKS2.lean:3288 to 3301
Mathematical statement
Exact Lean statement
lemma tendsto_log_div_self_mul_integral_atTop_zero {x₁ : ℝ} (hx₁ : 14 ≤ x₁) :
Filter.Tendsto (fun y ↦ (Real.log y / y) * ∫ s in x₁..y, 1 / (Real.log s) ^ 2) Filter.atTop (nhds 0)Complete declaration
Lean source
Full Lean sourceLean 4
lemma tendsto_log_div_self_mul_integral_atTop_zero {x₁ : ℝ} (hx₁ : 14 ≤ x₁) : Filter.Tendsto (fun y ↦ (Real.log y / y) * ∫ s in x₁..y, 1 / (Real.log s) ^ 2) Filter.atTop (nhds 0) := by have h_lim : Filter.Tendsto (fun y ↦ Real.log x₁ / (Real.log x₁ - 2) / Real.log y) Filter.atTop (nhds 0) := by have h_inv : Filter.Tendsto (fun y ↦ (Real.log y)⁻¹) Filter.atTop (nhds 0) := Filter.Tendsto.comp tendsto_inv_atTop_zero Real.tendsto_log_atTop have := tendsto_const_nhds (x := Real.log x₁ / (Real.log x₁ - 2)) |>.mul h_inv simp only [mul_zero] at this rwa [show (fun x ↦ Real.log x₁ / (Real.log x₁ - 2) * (Real.log x)⁻¹) = (fun y ↦ Real.log x₁ / (Real.log x₁ - 2) / Real.log y) by ext y; ring] at this refine tendsto_of_tendsto_of_tendsto_of_le_of_le' tendsto_const_nhds h_lim ?_ ?_ · filter_upwards [Filter.eventually_ge_atTop x₁] with y hy exact log_div_self_mul_integral_nonneg hx₁ hy · filter_upwards [Filter.eventually_ge_atTop x₁] with y hy exact log_div_self_mul_integral_le_of_ge hx₁ hy