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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 2 |
| 3 | -3 |
| 4 | 23 |
| 5 | -130 |
| 6 | 1016 |
| 7 | -8925 |
| 8 | 90369 |
| 9 | -1027332 |
| 10 | 12980406 |
| 11 | -180372995 |
| 12 | 2734039527 |
| 13 | -44890794078 |
| 14 | 793705143908 |
| 15 | -15034678005165 |
| 16 | 303761462921921 |
| 17 | -6520477426903400 |
| 18 | 148194700045065674 |
| 19 | -3555110881720345347 |
[1,0,2,-3,23,-130,1016,-8925,90369,-1027332, 12980406,-180372995,2734039527,-44890794078, 793705143908,-15034678005165,303761462921921, -6520477426903400,148194700045065674, -3555110881720345347] |