AlexKontorovich/PrimeNumberTheoremAnd
Source indexedtheorem · leanprover/lean4:v4.32.0
BKLNW.prop_3_sub_3
PrimeNumberTheoremAnd.IEANTN.BKLNW.BKLNW · PrimeNumberTheoremAnd/IEANTN/BKLNW/BKLNW.lean:326 to 339
Mathematical statement
Exact Lean statement
@[blueprint "bklnw-prop-3-sub-3" (title := "BKLNW Proposition 3, substep 3") (statement := /-- $f(2^n) = 1 + u_n$.-/) (proof := /-- Clear. -/) (latexEnv := "sublemma") (discussion := 633)] theorem prop_3_sub_3 (n : ℕ) (hn : n ≥ 3) : f (2^n) = 1 + u n
Complete declaration
Lean source
Full Lean sourceLean 4
@[blueprint "bklnw-prop-3-sub-3" (title := "BKLNW Proposition 3, substep 3") (statement := /-- $f(2^n) = 1 + u_n$.-/) (proof := /-- Clear. -/) (latexEnv := "sublemma") (discussion := 633)]theorem prop_3_sub_3 (n : ℕ) (hn : n ≥ 3) : f (2^n) = 1 + u n := by have sum_bound : ⌊ (log (2 ^ n)) / (log 2) ⌋₊ = n := by norm_num rw [f, u, sum_bound, ← add_sum_Ioc_eq_sum_Icc hn, ← Icc_add_one_left_eq_Ioc, Nat.cast_ofNat, sub_self, rpow_zero] congr with k rw [← rpow_natCast _ n, ← rpow_mul (by norm_num)] field_simp