| ∀ n, m. sum-of-differences(n, bag0 -- m) = (m ∈ bag0 ⊃ sum-of-differences(n, bag0) - (n - m);sum-of-differences(n, bag0)) ⊦ (n - vtblpnum) + sum-of-differences(n, bag0 -- m) = (m ∈ bag0 ++ vtblpnum ⊃ (n - vtblpnum) + sum-of-differences(n, bag0) - (n - m);(n - vtblpnum) + sum-of-differences(n, bag0)), vtblpnum = m |
m ∈ bag0 ++ vtblpnum, ∀ n, m. sum-of-differences(n, bag0 -- m) = (m ∈ bag0 ⊃ sum-of-differences(n, bag0) - (n - m);sum-of-differences(n, bag0)) ⊦ (n - vtblpnum) + sum-of-differences(n, bag0 -- m) = (n - vtblpnum) + sum-of-differences(n, bag0) - (n - m), vtblpnum = m
∀ n, m. sum-of-differences(n, bag0 -- m) = (m ∈ bag0 ⊃ sum-of-differences(n, bag0) - (n - m);sum-of-differences(n, bag0)) ⊦ (n - vtblpnum) + sum-of-differences(n, bag0 -- m) = (n - vtblpnum) + sum-of-differences(n, bag0), vtblpnum = m, m ∈ bag0 ++ vtblpnum