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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 0 |
| 7 | 0 |
| 8 | 1 |
| 9 | 16 |
| 10 | 272 |
| 11 | 2880 |
| 12 | 32648 |
| 13 | 333696 |
| 14 | 3617545 |
| 15 | 38942336 |
| 16 | 443291226 |
| 17 | 5168682752 |
| 18 | 63523977424 |
| 19 | 807890646528 |
| 20 | 10790865576074 |
| 21 | 149552304296960 |
| 22 | 2168856599259491 |
| 23 | 32631738808727552 |
| 24 | 512002155247238968 |
[1,1,0,0,0,0,0,0,1,16,272,2880,32648,333696, 3617545,38942336,443291226,5168682752,63523977424, 807890646528,10790865576074,149552304296960, 2168856599259491,32631738808727552, 512002155247238968] |