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