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