| ∀ n. (∀ n0. count(n0, (bag0 -- n) ++ n) = count(n0, bag0)) ↔ count(n, bag0) ≠ 0 ⊦ (∀ n0. count(n0, (m = n ⊃ bag0;(bag0 -- n) ++ m) ++ n) = count(n0, bag0 ++ m)) ↔ count(n, bag0 ++ m) ≠ 0 |
⊦ count(n, bag0 ++ n0) = (n = n0 ⊃ 1;0) + count(n, bag0)
∀ n. (∀ n0. count(n0, (bag0 -- n) ++ n) = count(n0, bag0)) ↔ count(n, bag0) ≠ 0 ⊦ (∀ n0. count(n0, (m = n ⊃ bag0;(bag0 -- n) ++ m) ++ n) = count(n0, bag0 ++ m)) ↔ (n = m ⊃ 1;0) + count(n, bag0) ≠ 0
Used terms: m, bag0, n