n0 < n ⊦ n < m * n ↔ m ≠ 0 ∧ m ≠ 1
Used simplifier rules: ⊦ m < n → n ≠ 0; (s)%f: ⊦ m < n → n ≠ 0; (forward) from specification nat-basic% ⊦ 1 < m ↔ ¬(m = 0 ∨ m = 1); (s)