| #oc(a, x) + #oc(a, y) = m + 1, a ∈ y ⊦ #oc(a, (x + y) -1l a) = m |
⊦ a ∈ x → #oc(a, x -1l a) = #oc(a, x) -1
Used simplifier rules: ocappend: ⊦ #oc(a, x + y) = #oc(a, x) + #oc(a, y);%ocappend: ⊦ #oc(a, x + y) = #oc(a, x) + #oc(a, y);%a: ⊦ (x + y) + z = x + y + z; from specification list% ⊦ n -1 = n - 1; (s)% ⊦ a ∈ y → a ∈ x + y; (s)% ⊦ n ≤ m → m + n0 - n = (m - n) + n0; (s)% ⊦ n + 0 = n; (s)%a: ⊦ (m + n0) + n1 = m + n0 + n1; from specification nat-basic%c: ⊦ m + n = n + m; from specification nat-basic% ⊦ ¬ a ∈ x → x -1l a = x; (s) Used terms: x + y, a