AlexKontorovich/PrimeNumberTheoremAnd
Source indexedtheorem · leanprover/lean4:v4.32.0
li.two_approx
PrimeNumberTheoremAnd.IEANTN.SecondaryDefinitions · PrimeNumberTheoremAnd/IEANTN/SecondaryDefinitions.lean:202 to 217
Mathematical statement
Exact Lean statement
@[blueprint
"Ramanujan-Soldner-constant"
(title := "Ramanujan-Soldner constant")
(statement := /-- $\li(2) = 1.0451\dots$. -/)
(proof := /--
Symmetrize the integral and use and some
numerical integration. -/)
(latexEnv := "lemma")
(discussion := 759)]
theorem li.two_approx : li 2 ∈ Set.Icc 1.0451 1.0452Complete declaration
Lean source
Full Lean sourceLean 4
@[blueprint "Ramanujan-Soldner-constant" (title := "Ramanujan-Soldner constant") (statement := /-- $\li(2) = 1.0451\dots$. -/) (proof := /-- Symmetrize the integral and use and some numerical integration. -/) (latexEnv := "lemma") (discussion := 759)] theorem li.two_approx : li 2 ∈ Set.Icc 1.0451 1.0452 := by rw [li_eq_eulerMascheroni_add_log_log_add_tsum (show (1 : ℝ) < 2 by norm_num)] have hll_lo : (-0.366513 : ℝ) ≤ Real.log (Real.log 2) := LogTables.log_log_2_gt have hll_hi : Real.log (Real.log 2) ≤ -0.366512 := LogTables.log_log_2_lt constructor <;> linarith [hs_lo, hs_hi, hγ_lo, hγ_hi]