| unique-elems(bag) ⊦ count(m, bag) - (m = n ∧ count(n, bag) ≠ 0 ⊃ 1;0) = 0, m ≠ n ∧ m ∈ bag |
m = n, unique-elems(bag) ⊦ count(m, bag) - 1 = 0, count(n, bag) = 0, m ≠ n ∧ m ∈ bag
unique-elems(bag), m ≠ n ∨ count(n, bag) = 0 ⊦ count(m, bag) - 0 = 0, m ≠ n ∧ m ∈ bag