| i0 * j + j0 - 1 = (j0 - 1) + i0 * j, j0 < j, 0 < j, 0 ≤ j, 0 ≤ i0, 0 ≤ i0 * j + j0, 0 < i0 * j + j0, 0 < j0, 1 < j ⊦ j0 = 0, (i0 * j + j0 - 1) / j = i0 |
j0 < j, 0 < j, 0 ≤ j, 0 ≤ i0, 0 ≤ i0 * j + j0, 0 < i0 * j + j0, 0 < j0, 1 < j ⊦ j0 = 0, ((j0 - 1) + i0 * j) / j = i0