| ∀ y. rmdup(x0 + rmdup(y)) = rmdup(x0 + y), a ∈ x0 ∨ a ∈ y ⊦ a ∈ rmdup(y), rmdup(x0 + rmdup(y)) = rmdup((a ' + x0) + y) |
a ∈ x0, ∀ y. rmdup(x0 + rmdup(y)) = rmdup(x0 + y) ⊦ rmdup(x0 + rmdup(y)) = rmdup(x0 + y), a ∈ y
Used simplifier rules: rm-in-02: ⊦ a ∈ rmdup(x) ↔ a ∈ x;%rm-in-05: ⊦ a ∈ x → rmdup(a ' + x + y) = rmdup(x + y);%a: ⊦ (x + y) + z = x + y + z; from specification list