⊦ odd(n) → (m = n / 2 ↔ n = m + m + 1)
2 * m0 = m * n ⊦ odd(n), 2 * n / 2 = n, ∃ m0. 2 * m0 = m
n = m1 + m1 + 1 ∧ odd(n), 2 * m0 = m * n ⊦ 2 * m1 = n, ∃ m0. 2 * m0 = m
Used terms: n, m1