unfold_let a
n : ℕ
hn : n ≠ 0
b : ℕ × ℕ
hb : (b.1 ∈ n.divisors ∧ b.2 ∈ n.divisors) ∧ b.1.lcm b.2 = n
g : ℕ := b.1.gcd b.2
a : Fin (succ 0).succ.succ → ℕ := ![g, b.1 / g, b.2 / g]
⊢ a 0 * a 1 * a 2 = n
n : ℕ
hn : n ≠ 0
b : ℕ × ℕ
hb : (b.1 ∈ n.divisors ∧ b.2 ∈ n.divisors) ∧ b.1.lcm b.2 = n
g : ℕ := b.1.gcd b.2
a : Fin (succ 0).succ.succ → ℕ := ![g, b.1 / g, b.2 / g]
⊢ ![g, b.1 / g, b.2 / g] 0 * ![g, b.1 / g, b.2 / g] 1 * ![g, b.1 / g, b.2 / g] 2 = n