| m ≤ n, n ≤ # x, m ≤ # x ⊦ x to n to m = x to m |
m ≤ # x, n0 +1 ≤ # x, m ≤ n0 +1, ∀ m, x. m ≤ n0 ∧ n0 ≤ # x ∧ m ≤ # x → x to n0 to m = x to m ⊦ x to n0 +1 to m = x to m
Used simplifier rules: to-zero-l: ⊦ x to 0 = [];%nat freely generated by 0, +1;;% ⊦ m ≤ 0 ↔ m = 0; (s)% ⊦ 0 ≤ m; (s)