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