AlexKontorovich/PrimeNumberTheoremAnd
Source indexedlemma · leanprover/lean4:v4.32.0
integrableOn_of_Zeta0_fun_log
PrimeNumberTheoremAnd.ZetaBounds · PrimeNumberTheoremAnd/ZetaBounds.lean:1135 to 1163
Mathematical statement
Exact Lean statement
lemma integrableOn_of_Zeta0_fun_log {N : ℕ} (Npos : 0 < N) {s : ℂ} (s_re_gt : 0 < s.re) :
IntegrableOn (fun (x : ℝ) ↦ (⌊x⌋ + 1 / 2 - x) * (x : ℂ) ^ (-(s + 1)) * (-Real.log x)) (Ioi N)
volumeComplete declaration
Lean source
Full Lean sourceLean 4
lemma integrableOn_of_Zeta0_fun_log {N : ℕ} (Npos : 0 < N) {s : ℂ} (s_re_gt : 0 < s.re) : IntegrableOn (fun (x : ℝ) ↦ (⌊x⌋ + 1 / 2 - x) * (x : ℂ) ^ (-(s + 1)) * (-Real.log x)) (Ioi N) volume := by simp_rw [mul_assoc] obtain ⟨c, hc⟩ := ZetaSum_aux2a apply Integrable.bdd_mul (c := c) ?_ ?_ ?_ · simp only [neg_add_rev, mul_neg, add_comm, ← sub_eq_add_neg] apply integrable_norm_iff ?_ |>.mp ?_ |>.neg · apply ContinuousOn.mul ?_ ?_ |>.aestronglyMeasurable (by simp) · intro x hx apply ContinuousWithinAt.cpow ?_ continuous_const.continuousWithinAt ?_ · exact RCLike.continuous_ofReal.continuousWithinAt · simp only [ofReal_mem_slitPlane]; linarith [mem_Ioi.mp hx] · apply RCLike.continuous_ofReal.continuousOn.comp ?_ (mapsTo_image _ _) refine continuous_id.continuousOn.log ?_ intro x hx; simp only [id_eq]; linarith [mem_Ioi.mp hx] · simp only [norm_mul, norm_real] have := integrable_log_over_pow (r := -s.re) (by linarith) Npos apply IntegrableOn.congr_fun this ?_ (by simp) intro x hx simp only [mul_eq_mul_right_iff, norm_eq_zero, Real.log_eq_zero] left have xpos : 0 < x := by linarith [mem_Ioi.mp hx] simp [norm_cpow_eq_rpow_re_of_pos xpos, Real.abs_rpow_of_nonneg xpos.le, abs_eq_self.mpr xpos.le] · apply Measurable.add ?_ measurable_const |>.sub (by fun_prop) |>.aestronglyMeasurable exact Measurable.comp (fun _ _ ↦ trivial) Int.measurable_floor · apply MeasureTheory.ae_of_all convert hc with _ x; simp only [← Complex.norm_real]; simp