| 100 | n | = | n | ( | n | + | 1 | ) | ( | 2 | n | + | 1 | ) | ÷ | 6 |
| 方程右边 = | n | n | ( | 2 | n | + | 1 | ) | × | 1 6 | + | n | × | 1 | ( | 2 | n | + | 1 | ) | × | 1 6 |
| = | n | n | ( | 2 | n | + | 1 | ) | × | 1 6 | + | n | × | 1 6 | ( | 2 | n | + | 1 | ) |
| = | n | n | × | 2 | n | × | 1 6 | + | n | n | × | 1 | × | 1 6 | + | n | × | 1 6 | ( | 2 | n | + | 1 | ) |
| = | n | n | × | 1 3 | n | + | n | n | × | 1 6 | + | n | × | 1 6 | ( | 2 | n | + | 1 | ) |
| = | n | n | × | 1 3 | n | + | n | n | × | 1 6 | + | n | × | 1 6 | × | 2 | n | + | n |
| = | n | n | × | 1 3 | n | + | n | n | × | 1 6 | + | n | × | 1 3 | n | + | n | × | 1 6 |
| 100 | n | = | n | n | × | 1 3 | n | + | n | n | × | 1 6 | + | n | × | 1 3 | n | + | 1 6 | n |