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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 2 |
| 5 | 1 |
| 6 | 10 |
| 7 | 15 |
| 8 | 26 |
| 9 | 91 |
| 10 | 180 |
| 11 | 375 |
| 12 | 1161 |
| 13 | 2388 |
| 14 | 5361 |
| 15 | 14924 |
| 16 | 31968 |
| 17 | 70100 |
| 18 | 183495 |
| 19 | 391848 |
| 20 | 862189 |
| 21 | 2120403 |
| 22 | 4548763 |
| 23 | 9920865 |
| 24 | 23395129 |
| 25 | 49909285 |
| 26 | 107873523 |
| 27 | 245586962 |
| 28 | 520810166 |
| 29 | 1113291924 |
| 30 | 2467392165 |
| 31 | 5191086795 |
| 32 | 10980884007 |
[1,1,2,2,1,10,15,26,91,180,375,1161,2388,5361, 14924,31968,70100,183495,391848,862189,2120403, 4548763,9920865,23395129,49909285,107873523, 245586962,520810166,1113291924,2467392165, 5191086795,10980884007] |