| j ≤ i, 0 < j, 0 < i, fac(i - j) * fac(j) | fac(i), 0 ≤ j, 0 ≤ i ⊦ binom_coef(i, j) * j = binom_coef(i, j - 1) * (i + 1 - j) |
⊦ i ≤ j ∧ 0 ≤ i → fac(j - i) * fac(i) | fac(j)
j - 1 ≤ i ∧ 0 ≤ j - 1 → fac(i - (j - 1)) * fac(j - 1) | fac(i), j ≤ i, 0 < j, 0 < i, fac(i - j) * fac(j) | fac(i), 0 ≤ j, 0 ≤ i ⊦ binom_coef(i, j) * j = binom_coef(i, j - 1) * (i + 1 - j)
Used terms: j - 1, i