| n0 ≤ #(x to n0), n0 < # x, ∀ m, x. m ≤ n0 ∧ n0 ≤ # x ∧ m ≤ # x → x to n0 to m = x to m ⊦ x = [], x to n0 to n0 = x to n0 |
n0 < # x, ∀ m, x. m ≤ n0 ∧ n0 ≤ # x ∧ m ≤ # x → x to n0 to m = x to m ⊦ x = [], x to n0 to n0 = x to n0
Used simplifier rules: length-to: ¬ # x < n ⊦ #(x to n) = n;%ler: ⊦ m ≤ m; from specification nat%ls-02: ⊦ m < n → ¬ n < m; from specification nat-basic1