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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 6 |
| 5 | 14 |
| 6 | 38 |
| 7 | 113 |
| 8 | 356 |
| 9 | 1164 |
| 10 | 3906 |
| 11 | 13364 |
| 12 | 46426 |
| 13 | 163294 |
| 14 | 580316 |
| 15 | 2080475 |
| 16 | 7515038 |
| 17 | 27324014 |
| 18 | 99920756 |
| 19 | 367264130 |
| 20 | 1356043388 |
| 21 | 5027345564 |
| 22 | 18706888196 |
| 23 | 69841532210 |
| 24 | 261545298848 |
| 25 | 982175296016 |
| 26 | 3697785571820 |
| 27 | 13954630170720 |
| 28 | 52776659865348 |
| 29 | 200006396351216 |
| 30 | 759386612309146 |
| 31 | 2888310863702017 |
[1,2,3,6,14,38,113,356,1164,3906,13364,46426, 163294,580316,2080475,7515038,27324014,99920756, 367264130,1356043388,5027345564,18706888196, 69841532210,261545298848,982175296016, 3697785571820,13954630170720,52776659865348, 200006396351216,759386612309146,2888310863702017] |