| ⊦ x ⊆m a ' + y ↔ #oc(a, x) ≤ #oc(a, y) + 1 ∧ x -1l a ⊆m y |
∀ a, y. x0 ⊆m a ' + y ↔ #oc(a, x0) ≤ #oc(a, y) + 1 ∧ x0 -1l a ⊆m y ⊦ a0 + x0 ⊆m a ' + y ↔ #oc(a, a0 + x0) ≤ #oc(a, y) + 1 ∧ (a0 + x0) -1l a ⊆m y
Used simplifier rules: subempty: ⊦ [] ⊆m x;%oc-e: ⊦ #oc(a, []) = 0;%list freely generated by [], +;;%lez: ⊦ 0 ≤ m; from specification nat%del1-e: ⊦ [] -1l a = []; from specification list-del