| disj(x, y + z) ⊦ disj(x, y) |
disj(x, (a + y0) + z), ∀ x, z. disj(x, y0 + z) → disj(x, y0) ⊦ disj(x, a + y0)
Used simplifier rules: e: ⊦ disj(x, []);%list freely generated by [], +;;% ⊦ [] + x = x; (s)%a: ⊦ (x + y) + z = x + y + z; from specification list