refine' le_trans _ (primorial_le_4_pow (2 * n / 3))
case h₂
n : ℕ
n_big : 2 < n
no_prime : ¬∃ p, p.Prime ∧ n < p ∧ p ≤ 2 * n
n_pos : 0 < n
n2_pos : 1 ≤ 2 * n
S : Finset ℕ := Finset.filter Nat.Prime (Finset.range (2 * n / 3 + 1))
f : ℕ → ℕ := fun x => x ^ n.centralBinom.factorization x
this : ∏ x ∈ S, f x = ∏ x ∈ Finset.range (2 * n / 3 + 1), f x
⊢ ∏ x ∈ Finset.filter (fun x => ¬x ≤ (2 * n).sqrt) S, f x ≤ 4 ^ (2 * n / 3)
case h₂
n : ℕ
n_big : 2 < n
no_prime : ¬∃ p, p.Prime ∧ n < p ∧ p ≤ 2 * n
n_pos : 0 < n
n2_pos : 1 ≤ 2 * n
S : Finset ℕ := Finset.filter Nat.Prime (Finset.range (2 * n / 3 + 1))
f : ℕ → ℕ := fun x => x ^ n.centralBinom.factorization x
this : ∏ x ∈ S, f x = ∏ x ∈ Finset.range (2 * n / 3 + 1), f x
⊢ ∏ x ∈ Finset.filter (fun x => ¬x ≤ (2 * n).sqrt) S, f x ≤ primorial (2 * n / 3)