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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | -4 |
| 3 | 33 |
| 4 | -376 |
| 5 | 5255 |
| 6 | -85392 |
| 7 | 1566656 |
| 8 | -31869104 |
| 9 | 710089551 |
| 10 | -17178977940 |
| 11 | 448256023501 |
| 12 | -12548355934560 |
| 13 | 375195009917364 |
| 14 | -11936772609109600 |
| 15 | 402740733371490540 |
| 16 | -14367278506882083936 |
| 17 | 540452504929440595503 |
| 18 | -21384560213508955184172 |
[1,1,-4,33,-376,5255,-85392,1566656,-31869104, 710089551,-17178977940,448256023501, -12548355934560,375195009917364, -11936772609109600,402740733371490540, -14367278506882083936,540452504929440595503, -21384560213508955184172] |