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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 0 |
| 3 | 3 |
| 4 | -12 |
| 5 | 65 |
| 6 | -450 |
| 7 | 3577 |
| 8 | -32424 |
| 9 | 331137 |
| 10 | -3757350 |
| 11 | 46892681 |
| 12 | -638447436 |
| 13 | 9416929249 |
| 14 | -149581289130 |
| 15 | 2545707159465 |
| 16 | -46213451575248 |
| 17 | 891368532889601 |
| 18 | -18204123410896590 |
| 19 | 392431030262264329 |
| 20 | -8904987308885931060 |
| 21 | 212174197452256551393 |
| 22 | -5296088301994320448530 |
[0,1,0,3,-12,65,-450,3577,-32424,331137,-3757350, 46892681,-638447436,9416929249,-149581289130, 2545707159465,-46213451575248,891368532889601, -18204123410896590,392431030262264329, -8904987308885931060,212174197452256551393, -5296088301994320448530] |