conv => change 2*(n <<< k).lsb = (2* (n <<< k)).lsb
this : ∀ (n : Nat), 2 * Nat.lsb n = Nat.lsb (2 * n)
k : Nat
h_ind : ∀ (n : Nat), Nat.lsb n <<< k = Nat.lsb (n <<< k)
n : Nat
⊢ Nat.lsb (n <<< k) <<< 1 = Nat.lsb (n <<< k <<< 1)
this : ∀ (n : Nat), 2 * Nat.lsb n = Nat.lsb (2 * n)
k : Nat
h_ind : ∀ (n : Nat), Nat.lsb n <<< k = Nat.lsb (n <<< k)
n : Nat
⊢ 2 * Nat.lsb (n <<< k) = Nat.lsb (2 * n <<< k)