| m ≠ 0, m1 ≤ # x0, m ≤ m1 + 1, m ≤ # x0 + 1, ∀ n, m, m0, n0. n + m ≤ m0 ∧ n0 + m0 ≤ # x0 → firstn(m, restn(n, firstn(m0, restn(n0, x0)))) = firstn(m, restn(n0 + n, x0)) ⊦ (a ' + firstn(m1, x0)).first ' + firstn(m -1, (a ' + firstn(m1, x0)).rest) = firstn(m, a ' + x0) |
m1 ≤ # x0, m ≤ m1 + 1, m ≤ # x0 + 1, ∀ n, m, m0, n0. n + m ≤ m0 ∧ n0 + m0 ≤ # x0 → firstn(m, restn(n, firstn(m0, restn(n0, x0)))) = firstn(m, restn(n0 + n, x0)) ⊦ m = 0, a ' + firstn(m - 1, firstn(m1, x0)) = firstn(m, a ' + x0)
Used simplifier rules: c-07: ⊦ (a ' + x).rest = x; from specification list%pred-03: ⊦ n -1 = n - 1; from specification nat%a: ⊦ (x + y) + z = x + y + z; from specification list%c-08: ⊦ (a ' + x).first = a; from specification list