m * n2 = m * n1 + n3, n2 < n1 ⊦ m * (n2 - n1) = n3, n1 = 0
Used simplifier rules: f: ⊦ m < n → n ≠ 0; (forward) from specification nat-basic1%lels-01: ⊦ ¬ m ≤ n ↔ n < m; from specification nat