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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 2 |
| 3 | -3 |
| 4 | 18 |
| 5 | -150 |
| 6 | 1518 |
| 7 | -17541 |
| 8 | 223782 |
| 9 | -3087948 |
| 10 | 45470022 |
| 11 | -707810715 |
| 12 | 11569008816 |
| 13 | -197540043324 |
| 14 | 3509923686678 |
| 15 | -64697804055675 |
| 16 | 1234127209128306 |
| 17 | -24312707152663590 |
| 18 | 493834352052852738 |
| 19 | -10327320248199824889 |
| 20 | 222086739445484152590 |
[0,1,2,-3,18,-150,1518,-17541,223782,-3087948, 45470022,-707810715,11569008816,-197540043324, 3509923686678,-64697804055675,1234127209128306, -24312707152663590,493834352052852738, -10327320248199824889,222086739445484152590] |