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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 7 |
| 5 | 14 |
| 6 | 41 |
| 7 | 107 |
| 8 | 337 |
| 9 | 1066 |
| 10 | 3691 |
| 11 | 12962 |
| 12 | 49061 |
| 13 | 188894 |
| 14 | 766845 |
| 15 | 3182844 |
| 16 | 13758383 |
| 17 | 60858842 |
| 18 | 278312475 |
| 19 | 1301323108 |
| 20 | 6258671365 |
| 21 | 30742575588 |
| 22 | 154785692507 |
| 23 | 794888735945 |
| 24 | 4173162573277 |
| 25 | 22318859784416 |
| 26 | 121767607626621 |
| 27 | 676010926754742 |
[1,1,2,3,7,14,41,107,337,1066,3691,12962,49061, 188894,766845,3182844,13758383,60858842,278312475, 1301323108,6258671365,30742575588,154785692507, 794888735945,4173162573277,22318859784416, 121767607626621,676010926754742] |