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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 8 |
| 2 | 288 |
| 3 | 6672 |
| 4 | 65840 |
| 5 | 391320 |
| 6 | 1681008 |
| 7 | 5767328 |
| 8 | 16781472 |
| 9 | 43053480 |
| 10 | 100010240 |
| 11 | 214373808 |
| 12 | 430002768 |
| 13 | 815759672 |
| 14 | 1475827920 |
| 15 | 2562941760 |
| 16 | 4295033408 |
| 17 | 6975841608 |
| 18 | 11020066272 |
| 19 | 16983694160 |
| 20 | 25600160880 |
| 21 | 37823054808 |
| 22 | 54876108848 |
[0,8,288,6672,65840,391320,1681008,5767328, 16781472,43053480,100010240,214373808,430002768, 815759672,1475827920,2562941760,4295033408, 6975841608,11020066272,16983694160,25600160880, 37823054808,54876108848] |