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| n | a(n) |
|---|---|
| 0 | 3 |
| 1 | 3 |
| 2 | 2 |
| 3 | 0 |
| 4 | 0 |
| 5 | 16 |
| 6 | 96 |
| 7 | 384 |
| 8 | 1280 |
| 9 | 3840 |
| 10 | 10752 |
| 11 | 28672 |
| 12 | 73728 |
| 13 | 184320 |
| 14 | 450560 |
| 15 | 1081344 |
| 16 | 2555904 |
| 17 | 5963776 |
| 18 | 13762560 |
| 19 | 31457280 |
| 20 | 71303168 |
| 21 | 160432128 |
| 22 | 358612992 |
| 23 | 796917760 |
| 24 | 1761607680 |
| 25 | 3875536896 |
| 26 | 8489271296 |
| 27 | 18522046464 |
| 28 | 40265318400 |
| 29 | 87241523200 |
| 30 | 188441690112 |
[3,3,2,0,0,16,96,384,1280,3840,10752,28672,73728, 184320,450560,1081344,2555904,5963776,13762560, 31457280,71303168,160432128,358612992,796917760, 1761607680,3875536896,8489271296,18522046464, 40265318400,87241523200,188441690112] |