| ∀ x. n0 ≤ # x → firstn(n0, x) + restn(n0, x) = x, n0 +1 ≤ # x ⊦ firstn(n0 +1, x) + restn(n0 +1, x) = x |
n0 < # x, ∀ x. n0 ≤ # x → firstn(n0, x) + restn(n0, x) = x ⊦ (x.first ' + firstn(n0, x.rest)) + restn(n0, x.rest) = x, x = []
Used simplifier rules: firstN-rec: ⊦ firstn(n + 1, x) = x.first + firstn(n, x.rest);%restN-rec: ⊦ restn(n + 1, x) = restn(n, x.rest);%l: ⊦ # x = 0 ↔ x = []; from specification list-data%f: ⊦ m < n → n ≠ 0; (forward) from specification nat-basic1%succ-01: ⊦ m + 1 ≤ n ↔ m < n; from specification nat%a: ⊦ (x + y) + z = x + y + z; from specification list%c: ⊦ m + n = n + m; from specification nat-basic2%a: ⊦ (m + n0) + n1 = m + n0 + n1; from specification nat-basic2%c: ⊦ a + x = a ' + x; from specification list%succ: ⊦ m +1 = m + 1; from specification nat-basic2