⊦ ∃ m0. 2 * m0 = m * n, ¬(∃ m0. 2 * m0 = m) ∧ ¬(∃ m0. 2 * m0 = n)
∃ m0. 2 * m0 = m * n ⊦ ∃ m0. 2 * m0 = n, ∃ m0. 2 * m0 = m