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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | -2 |
| 2 | -12 |
| 3 | 56 |
| 4 | 80 |
| 5 | -1056 |
| 6 | 832 |
| 7 | 15232 |
| 8 | -43776 |
| 9 | -156160 |
| 10 | 1012736 |
| 11 | 473088 |
| 12 | -17149952 |
| 13 | 26730496 |
| 14 | 220938240 |
| 15 | -869564416 |
| 16 | -1795883008 |
| 17 | 17504796672 |
| 18 | -6275465216 |
| 19 | -267525816320 |
| 20 | 635459076096 |
| 21 | 3009494908928 |
| 22 | -16186335035392 |
| 23 | -15779248472064 |
| 24 | 290539857510400 |
[1,-2,-12,56,80,-1056,832,15232,-43776,-156160, 1012736,473088,-17149952,26730496,220938240, -869564416,-1795883008,17504796672,-6275465216, -267525816320,635459076096,3009494908928, -16186335035392,-15779248472064,290539857510400] |