| 1 | 2 | 3 | n | n+2 | |||||
+ | + | +...+ | =2− | ||||||
| 2 | 22 | 23 | 2n | 2n |
| k+2 | ||
2− | +{k+1}{2k+1} | |
| 2k |
| k + 2 | k + 1 | k + 1 | ||||
2 − | + | = 2 − U{2k + 4}{2k + 1 + | = | |||
| 2k | 2k+1 | 2k+1 |
| k + 1 − 2k − 4 | − k − 3 | (k + 1) + 2 | ||||
= 2 + | = 2 + | = 2 − | ||||
| 2k + 1 | 2k + 1 | 2k+1 |
| n+1 | n+2 | n+1 | 2n+4 | ||||
− | = | − | |||||
| 2n+1 | 2n | 2n+1 | 2n+1 |
| n+3 | (n+1)+2 | |||
=− | =− | |||
| 2n+1 | 2n+1 |