| # rmdup(x + y + z) = # rmdup(x + z), a ∈ y ⊦ a ∈ z, a ∈ x |
# x = # y, ¬ dups(x), ¬ dups(y), ∀ a. a ∈ x → a ∈ y ⊦ ∀ a. a ∈ y → a ∈ x
# rmdup(x + y + z) = # rmdup(x + z), a ∈ y, ∀ a. a ∈ rmdup(x + y + z) → a ∈ rmdup(x + z) ⊦ a ∈ x, a ∈ z
Used simplifier rules: rm-nodups: ⊦ ¬ dups(rmdup(x));%rm-in: ⊦ a ∈ rmdup(x + y) ↔ a ∈ x ∨ a ∈ y;% ⊦ a ∈ x + y ↔ a ∈ x ∨ a ∈ y; (s)%a: ⊦ (x + y) + z = x + y + z; from specification list Used terms: rmdup(x + z), rmdup(x + y + z)