| fac(i - 1) / (fac(i - 1 + j) * j * fac(j - 1)) = ((i - j) * fac(i - 1)) / (fac(i - j) * j * fac(j - 1)), 0 ≤ fac(i - 1), fac(j - 1) * fac(i - j) | fac(i - 1), 1 < j, 1 < i, 0 < j, 0 ≤ i, j ≤ i, j < i, 0 < i, 0 < fac(i - j) * fac(j - 1) ⊦ fac(i) / (fac(i - j) * j * fac(j - 1)) = fac(i - 1) / (fac(i - j) * fac(j - 1)) + ((i - j) * fac(i - 1)) / (fac(i - j) * j * fac(j - 1)), fac(i - 1) % (fac(i - j) * fac(j - 1)) = 0, j = 0 |
⊦ j | i ∧ i ≠ 0 → i % j = 0
Used simplifier rules: fac-zero-02: ⊦ fac(i) ≠ 0;%commutativity: ⊦ i * j = j * i; from specification int-mult Used terms: fac(i - j) * fac(j - 1), fac(i - 1)