| ¬ a ∈ x0 + rmdup(y), ∀ y. rmdup(x0 + rmdup(y)) = rmdup(x0 + y) ⊦ rmdup((a ' + x0) + rmdup(y)) = rmdup((a ' + x0) + y) |
∀ y. rmdup(x0 + rmdup(y)) = rmdup(x0 + y) ⊦ a ' + rmdup(x0 + rmdup(y)) = rmdup((a ' + x0) + y), a ∈ x0, a ∈ y
Used simplifier rules: rmdup-n: ⊦ ¬ a ∈ x → rmdup(a ' + x) = a + rmdup(x);%rm-in-02: ⊦ a ∈ rmdup(x) ↔ a ∈ x;%in-append: ⊦ a ∈ x + y ↔ ¬ ¬(a ∈ x ∨ a ∈ y); from specification list%a: ⊦ (x + y) + z = x + y + z; from specification list%c: ⊦ a + x = a ' + x; from specification list