| # x = # y, ∀ a. a ∈ y → a ∈ x, ∀ a. a ∈ x → a ∈ y ⊦ dups(y), dups(x), #oc(a, x) ≤ #oc(a, y) |
Used simplifier rules: oc-dups: ⊦ n < #oc(a, x) ∧ ¬ dups(x) → #oc(a, x) = 1;%oc-zero: ⊦ #oc(a, x) = 0 ↔ ¬ a ∈ x;% ⊦ m ≤ n ↔ ¬ n < m; (ss)%f: ⊦ m < n → n ≠ 0; (forward) from specification nat-basic%lf-01: ⊦ m < n ∧ n = n0 → m < n0; (forward) from specification nat-basic% ⊦ m < 1 ↔ m = 0; (s) Used terms: a