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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 1 |
| 3 | -3 |
| 4 | 4 |
| 5 | 0 |
| 6 | 16 |
| 7 | -168 |
| 8 | 64 |
| 9 | 3840 |
| 10 | 256 |
| 11 | -177408 |
| 12 | 1024 |
| 13 | 11182080 |
| 14 | 4096 |
| 15 | -951886848 |
| 16 | 16384 |
| 17 | 104932638720 |
| 18 | 65536 |
| 19 | -14544442687488 |
| 20 | 262144 |
| 21 | 2475749026037760 |
| 22 | 1048576 |
| 23 | -507711943255523328 |
| 24 | 4194304 |
| 25 | 123460740095095603200 |
| 26 | 16777216 |
[1,0,1,-3,4,0,16,-168,64,3840,256,-177408,1024, 11182080,4096,-951886848,16384,104932638720,65536, -14544442687488,262144,2475749026037760,1048576, -507711943255523328,4194304,123460740095095603200, 16777216] |