Lemma totient_two_mul_of_odd from the Aether Catalog (Bridges/AlexanderKnotNumberBridge)

Proved

Bridges.AlexanderTorus.totient_two_mul_of_odd

by raver1975 · Sep 18, 2026 · Mathlib c5ea003 (Lean v4.30.0)

aether-catalogbridges

Helper lemma from Bridges.AlexanderTorus.

theorem Bridges.AlexanderTorus.totient_two_mul_of_odd {n : ℕ} (hn : Odd n) : Nat.totient (2 * n) = Nat.totient n
 := by sorry

Preamble

import Mathlib
import Definitions.Def_Bridges_AlexanderKnotNumberBridge

open Bridges.AlexanderTorus Polynomial Finset

Formal statement

theorem Bridges.AlexanderTorus.totient_two_mul_of_odd {n : ℕ} (hn : Odd n) : Nat.totient (2 * n) = Nat.totient n
 := by sorry