| 0 < n, m + n ≤ 1 + # x0, ∀ m, n. m + n ≤ # x0 → lastn(m, restn(n, x0)) = lastn(m, x0) ⊦ lastn(m, restn(n -1, (a ' + x0).tail)) = lastn(m, a ' + x0) |
m + n ≤ 1 + # x0, ∀ m, n. m + n ≤ # x0 → lastn(m, restn(n, x0)) = lastn(m, x0) ⊦ lastn(m, restn(n - 1, x0)) = lastn(m, a ' + x0), n = 0
Used simplifier rules: ⊦ 0 < n ↔ n ≠ 0; (s)%a: ⊦ (x + y) + z = x + y + z; from specification list% ⊦ (a ' + x).tail = x; (s)% ⊦ n -1 = n - 1; (s)