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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 0 |
| 3 | 1 |
| 4 | 1 |
| 5 | 2 |
| 6 | 3 |
| 7 | 7 |
| 8 | 10 |
| 9 | 20 |
| 10 | 35 |
| 11 | 66 |
| 12 | 113 |
| 13 | 218 |
| 14 | 412 |
| 15 | 746 |
| 16 | 1460 |
| 17 | 2672 |
| 18 | 5104 |
| 19 | 9651 |
| 20 | 18375 |
| 21 | 35105 |
| 22 | 67165 |
| 23 | 128410 |
| 24 | 246453 |
| 25 | 473535 |
| 26 | 911489 |
| 27 | 1756670 |
| 28 | 3390856 |
| 29 | 6552449 |
| 30 | 12673142 |
| 31 | 24546849 |
| 32 | 47583904 |
| 33 | 92330578 |
| 34 | 179317889 |
| 35 | 348548185 |
| 36 | 678029708 |
| 37 | 1319939685 |
| 38 | 2571409639 |
[1,0,1,1,2,3,7,10,20,35,66,113,218,412,746,1460, 2672,5104,9651,18375,35105,67165,128410,246453, 473535,911489,1756670,3390856,6552449,12673142, 24546849,47583904,92330578,179317889,348548185, 678029708,1319939685,2571409639] |