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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 4 |
| 5 | 8 |
| 6 | 17 |
| 7 | 38 |
| 8 | 82 |
| 9 | 177 |
| 10 | 376 |
| 11 | 789 |
| 12 | 1638 |
| 13 | 3376 |
| 14 | 6894 |
| 15 | 13987 |
| 16 | 28181 |
| 17 | 56424 |
| 18 | 112282 |
| 19 | 222171 |
| 20 | 437098 |
| 21 | 855311 |
| 22 | 1664755 |
| 23 | 3223402 |
| 24 | 6209505 |
| 25 | 11901967 |
| 26 | 22700056 |
| 27 | 43083657 |
| 28 | 81376732 |
| 29 | 152971812 |
| 30 | 286199220 |
| 31 | 532954482 |
| 32 | 987861697 |
| 33 | 1822655134 |
[1,1,1,2,4,8,17,38,82,177,376,789,1638,3376,6894, 13987,28181,56424,112282,222171,437098,855311, 1664755,3223402,6209505,11901967,22700056, 43083657,81376732,152971812,286199220,532954482, 987861697,1822655134] |