| n ≤ m ⊦ n0 = m - n ↔ m = n0 + n |
∀ m, n0. n1 ≤ m → (n0 = m - n1 ↔ m = n0 + n1), n1 +1 ≤ m ⊦ n0 = m - n1 +1 ↔ m = n0 + n1 +1
Used simplifier rules: sub-base: ⊦ m - 0 = m;%nat freely generated by 0, +1;;%add-base: ⊦ n + 0 = n; from specification nat-basic2%a: ⊦ (m + n0) + n1 = m + n0 + n1; from specification nat-basic2%c: ⊦ m + n = n + m; from specification nat-basic2