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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | -6 |
| 3 | 28 |
| 4 | -138 |
| 5 | 828 |
| 6 | -5180 |
| 7 | 33528 |
| 8 | -223002 |
| 9 | 1512812 |
| 10 | -10423796 |
| 11 | 72743688 |
| 12 | -513005252 |
| 13 | 3649850584 |
| 14 | -26162987064 |
| 15 | 188758837488 |
| 16 | -1369529290618 |
| 17 | 9985780112460 |
| 18 | -73129564342212 |
| 19 | 537647977891688 |
| 20 | -3966638722824108 |
| 21 | 29357430489994120 |
| 22 | -217899481094085320 |
| 23 | 1621534636345991568 |
| 24 | -12095712639252241956 |
[1,2,-6,28,-138,828,-5180,33528,-223002,1512812, -10423796,72743688,-513005252,3649850584, -26162987064,188758837488,-1369529290618, 9985780112460,-73129564342212,537647977891688, -3966638722824108,29357430489994120, -217899481094085320,1621534636345991568, -12095712639252241956] |