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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 0 |
| 5 | -15 |
| 6 | -48 |
| 7 | -21 |
| 8 | 448 |
| 9 | 1953 |
| 10 | 640 |
| 11 | -32461 |
| 12 | -152064 |
| 13 | 77649 |
| 14 | 4331264 |
| 15 | 18557595 |
| 16 | -46686208 |
| 17 | -894805183 |
| 18 | -2948087808 |
| 19 | 21405607651 |
| 20 | 254321049600 |
| 21 | 421226202033 |
| 22 | -10904188190720 |
| 23 | -90171090228021 |
| 24 | 96102216892416 |
| 25 | 6418365899545825 |
[0,1,2,3,0,-15,-48,-21,448,1953,640,-32461, -152064,77649,4331264,18557595,-46686208, -894805183,-2948087808,21405607651,254321049600, 421226202033,-10904188190720,-90171090228021, 96102216892416,6418365899545825] |