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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 144 |
| 2 | -17712 |
| 3 | 524736 |
| 4 | -2279088 |
| 5 | -79760160 |
| 6 | 71126208 |
| 7 | 7093116288 |
| 8 | 65399933520 |
| 9 | 370698709968 |
| 10 | 1592500629600 |
| 11 | 5659924638528 |
| 12 | 17465468914368 |
| 13 | 48233085519456 |
| 14 | 121766302456704 |
| 15 | 285303917520000 |
| 16 | 627654170451024 |
| 17 | 1308136029869088 |
| 18 | 2601247015228176 |
[1,144,-17712,524736,-2279088,-79760160,71126208, 7093116288,65399933520,370698709968,1592500629600, 5659924638528,17465468914368,48233085519456, 121766302456704,285303917520000,627654170451024, 1308136029869088,2601247015228176] |