| ¬ a ∈ y0 \ z, ∀ z. rmdup(y0) \ z = rmdup(y0 \ z) ⊦ a ' + (rmdup(y0) \ z) = a + rmdup(y0 \ z), a ∈ y0, a ∈ z |
∀ z. rmdup(y0) \ z = rmdup(y0 \ z) ⊦ rmdup(y0) \ z = rmdup(y0 \ z), a ∈ z, a ∈ y0
Used simplifier rules: diff-in: ⊦ a ∈ x \ y ↔ a ∈ x ∧ ¬ a ∈ y;%a: ⊦ (x + y) + z = x + y + z; from specification list%app-08: ⊦ a ' + x = a ' + y ↔ x = y; from specification list%c: ⊦ a + x = a ' + x; from specification list