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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 0 |
| 7 | 0 |
| 8 | 0 |
| 9 | 0 |
| 10 | 1 |
| 11 | 4 |
| 12 | 19 |
| 13 | 77 |
| 14 | 287 |
| 15 | 1002 |
| 16 | 3365 |
| 17 | 10853 |
| 18 | 34088 |
| 19 | 104574 |
| 20 | 315116 |
| 21 | 935321 |
| 22 | 2743374 |
| 23 | 7966723 |
| 24 | 22951010 |
| 25 | 65681536 |
| 26 | 186961873 |
| 27 | 529845497 |
| 28 | 1496245171 |
| 29 | 4213181063 |
| 30 | 11836671278 |
| 31 | 33195092417 |
| 32 | 92966480736 |
[0,0,0,0,0,0,0,0,0,1,4,19,77,287,1002,3365,10853, 34088,104574,315116,935321,2743374,7966723, 22951010,65681536,186961873,529845497,1496245171, 4213181063,11836671278,33195092417,92966480736] |