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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 1 |
| 5 | 3 |
| 6 | 1 |
| 7 | 4 |
| 8 | 13 |
| 9 | 32 |
| 10 | 35 |
| 11 | 96 |
| 12 | 124 |
| 13 | 335 |
| 14 | 466 |
| 15 | 1116 |
| 16 | 1717 |
| 17 | 4371 |
| 18 | 6380 |
| 19 | 15490 |
| 20 | 23904 |
| 21 | 58041 |
| 22 | 88200 |
| 23 | 209875 |
| 24 | 331769 |
| 25 | 795599 |
| 26 | 1258386 |
| 27 | 2951789 |
| 28 | 4741344 |
| 29 | 11144763 |
| 30 | 17964801 |
| 31 | 41781268 |
| 32 | 68371012 |
| 33 | 158643268 |
[0,0,0,1,3,1,4,13,32,35,96,124,335,466,1116,1717, 4371,6380,15490,23904,58041,88200,209875,331769, 795599,1258386,2951789,4741344,11144763,17964801, 41781268,68371012,158643268] |