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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 4 |
| 6 | 7 |
| 7 | 12 |
| 8 | 25 |
| 9 | 55 |
| 10 | 115 |
| 11 | 245 |
| 12 | 564 |
| 13 | 1331 |
| 14 | 3103 |
| 15 | 7407 |
| 16 | 18388 |
| 17 | 46198 |
| 18 | 116503 |
| 19 | 299966 |
| 20 | 789426 |
| 21 | 2095941 |
| 22 | 5616114 |
| 23 | 15299205 |
| 24 | 42255533 |
| 25 | 117689096 |
| 26 | 331204936 |
| 27 | 944052610 |
| 28 | 2718150015 |
| 29 | 7891518587 |
| 30 | 23137661717 |
| 31 | 68524545717 |
| 32 | 204645635263 |
| 33 | 616098009473 |
[1,1,1,1,2,4,7,12,25,55,115,245,564,1331,3103, 7407,18388,46198,116503,299966,789426,2095941, 5616114,15299205,42255533,117689096,331204936, 944052610,2718150015,7891518587,23137661717, 68524545717,204645635263,616098009473] |