| 1 | 1 | 1 | ||||
L(k) = | + | +...+ | ||||
| k+1 | k+2 | 2k |
| 1 | 1 | 1 | 1 | 1 | ||||||
L(k+1) = | + | +...+ | + | + | ||||||
| k+2 | k+3 | 2k | 2k+1 | 2(k+1) |
| 1 | 1 | 1 | (2k+2)+(2k+1) | 1 | ||||||
L(k+1) = L(k)− | + | + | =L(k)+ | − | = | |||||
| k+1 | 2k+1 | 2(k+1) | (2k+1)(2k+2) | k+1 |
| 4k+3 | 1 | (4k+3)(k+1)−(2k+1)(2k+2) | ||||
=L(k)+ | − | =L(k)+ | = | |||
| (2k+1)(2k+2) | k+1 | (2k+1)(2k+2)(k+1) |
| (4k2+7k+3)−(4k2+6k+2) | k+1 | |||
=L(k)+ | =L(k)+ | = | ||
| (2k+1)(2k+2)(k+1) | (2k+1)(2k+2)(k+1) |
| 1 | 13 | |||
=L(k)+ | > L(k) > | |||
| (2k+1)(2k+2) | 24 |