intro x hxb hbx
n a b : ℕ
ha : a ≤ 2
⊢ ∀ (x : ℕ), x < b → (a ≤ x → b ≤ x) → x ^ ↑(Nat.factorization (Nat.centralBinom n)) x = 1
n a b : ℕ
ha : a ≤ 2
x : ℕ
hxb : x < b
hbx : a ≤ x → b ≤ x
⊢ x ^ ↑(Nat.factorization (Nat.centralBinom n)) x = 1