∀ a. max(ins≤(a, x0)) = max(x0) ∨ x0 = [] ∨ max(x0) < a ⊦ max(ins≤(a, a0 + x0)) = max(a0 + x0), a0 + x0 = [], max(a0 + x0) < a
Used simplifier rules: list freely generated by [], +;;