| ⊦ (∀ a. a ∈ x → a ∈ rmdup(y)) ↔ (∀ a. a ∈ x → a ∈ y) |
∀ x. (∀ a. a ∈ x → a ∈ rmdup(y0)) ↔ (∀ a. a ∈ x → a ∈ y0) ⊦ (∀ a0. a0 ∈ x → a0 ∈ rmdup(a + y0)) ↔ (∀ a0. a0 ∈ x → a0 ∈ a + y0)
Used simplifier rules: list freely generated by [], +;;%rmdup-e: ⊦ rmdup([]) = []; from specification list-dup%in-empty: ⊦ ¬ a ∈ []; from specification list