| ⊦ (x -1l a) -l b = (x -l b) -1l a, a = b |
∀ a, b. (x0 -1l a) -l b = (x0 -l b) -1l a ∨ a = b ⊦ ((a0 + x0) -1l a) -l b = ((a0 + x0) -l b) -1l a, a = b
Used simplifier rules: del1-e: ⊦ [] -1l a = [];%del-e: ⊦ [] -l a = [];%list freely generated by [], +;;