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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 1 |
| 3 | 0 |
| 4 | 2 |
| 5 | 3 |
| 6 | 0 |
| 7 | 16 |
| 8 | 30 |
| 9 | 15 |
| 10 | 0 |
| 11 | 272 |
| 12 | 588 |
| 13 | 420 |
| 14 | 105 |
| 15 | 0 |
| 16 | 7936 |
| 17 | 18960 |
| 18 | 16380 |
| 19 | 6300 |
| 20 | 945 |
| 21 | 0 |
| 22 | 353792 |
| 23 | 911328 |
| 24 | 893640 |
| 25 | 429660 |
| 26 | 103950 |
| 27 | 10395 |
| 28 | 0 |
| 29 | 22368256 |
| 30 | 61152000 |
| 31 | 65825760 |
| 32 | 36636600 |
| 33 | 11351340 |
| 34 | 1891890 |
| 35 | 135135 |
| 36 | 0 |
| 37 | 1903757312 |
[1,0,1,0,2,3,0,16,30,15,0,272,588,420,105,0,7936, 18960,16380,6300,945,0,353792,911328,893640, 429660,103950,10395,0,22368256,61152000,65825760, 36636600,11351340,1891890,135135,0,1903757312] |