conv => rhs; rw [mul_assoc]
case h
n : ℕ
hn : 2 < n
⊢ (∏ x in Finset.range (Nat.succ (Nat.sqrt (2 * n))), x ^ ↑(Nat.factorization (Nat.centralBinom n)) x) *
      ∏ x in Finset.Ioc (Nat.sqrt (2 * n)) (2 * n), x ^ ↑(Nat.factorization (Nat.centralBinom n)) x ≤
    (2 * n) ^ Nat.sqrt (2 * n) * 4 ^ Nat.pred (2 * n / 3) * ∏ p in primes (Finset.Ioc n (2 * n)), p
case h
n : ℕ
hn : 2 < n
⊢ (∏ x in Finset.range (Nat.succ (Nat.sqrt (2 * n))), x ^ ↑(Nat.factorization (Nat.centralBinom n)) x) *
      ∏ x in Finset.Ioc (Nat.sqrt (2 * n)) (2 * n), x ^ ↑(Nat.factorization (Nat.centralBinom n)) x ≤
    (2 * n) ^ Nat.sqrt (2 * n) * (4 ^ Nat.pred (2 * n / 3) * ∏ p in primes (Finset.Ioc n (2 * n)), p)