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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | -1 |
| 2 | 2 |
| 3 | -2 |
| 4 | 0 |
| 5 | 8 |
| 6 | 8 |
| 7 | -184 |
| 8 | 192 |
| 9 | 5568 |
| 10 | -20480 |
| 11 | -231552 |
| 12 | 1837696 |
| 13 | 11751296 |
| 14 | -187743488 |
| 15 | -596164352 |
| 16 | 22698672128 |
| 17 | 4342886400 |
| 18 | -3236847570944 |
| 19 | 10035384119296 |
| 20 | 536307107184640 |
| 21 | -3825733461393408 |
| 22 | -101121059849109504 |
[1,-1,2,-2,0,8,8,-184,192,5568,-20480,-231552, 1837696,11751296,-187743488,-596164352, 22698672128,4342886400,-3236847570944, 10035384119296,536307107184640,-3825733461393408, -101121059849109504] |