| ∀ a. (a ' + x0).butlast + (a ' + x0).last ' = a ' + x0 ⊦ (a ' + (a0 + x0)).butlast + (a ' + (a0 + x0)).last ' = a ' + (a0 + x0) |
∀ a. (a ' + x0).butlast + (a ' + x0).last ' = a ' + x0 ⊦ (a0 ' + x0).butlast + (a0 ' + x0).last ' = a0 ' + x0
Used simplifier rules: bin: ⊦ (x + a ' + y).butlast = x + (a ' + y).butlast;%lapp-01: ⊦ (x + a ' + y).last = (a ' + y).last;% ⊦ x + y = x + z ↔ y = z; (s)%a: ⊦ (x + y) + z = x + y + z; from specification list% ⊦ a + x = a ' + x; (s)