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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 2 |
| 6 | 5 |
| 7 | 13 |
| 8 | 34 |
| 9 | 90 |
| 10 | 241 |
| 11 | 652 |
| 12 | 1780 |
| 13 | 4899 |
| 14 | 13581 |
| 15 | 37893 |
| 16 | 106340 |
| 17 | 299978 |
| 18 | 850187 |
| 19 | 2419788 |
| 20 | 6913658 |
| 21 | 19822439 |
| 22 | 57015620 |
| 23 | 164476023 |
| 24 | 475752469 |
| 25 | 1379553027 |
| 26 | 4009532279 |
| 27 | 11678165796 |
| 28 | 34081307147 |
| 29 | 99646051271 |
| 30 | 291845778020 |
| 31 | 856147139606 |
| 32 | 2515368741707 |
| 33 | 7400713869808 |
| 34 | 21803597196231 |
[1,1,1,1,1,2,5,13,34,90,241,652,1780,4899,13581, 37893,106340,299978,850187,2419788,6913658, 19822439,57015620,164476023,475752469,1379553027, 4009532279,11678165796,34081307147,99646051271, 291845778020,856147139606,2515368741707, 7400713869808,21803597196231] |