| count(a, bag0 ++ a0) = 0, ∀ a. count(a, bag0) = 0 → bag0 -- a = bag0 ⊦ (bag0 -- a) ++ a0 = bag0 ++ a0, a0 = a |
count(a, bag0) = 0, ∀ a. count(a, bag0) = 0 → bag0 -- a = bag0 ⊦ (bag0 -- a) ++ a0 = bag0 ++ a0, a0 = a
Used simplifier rules: ⊦ a ≠ b → count(a, bag ++ b) = count(a, bag); (s)