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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | -1 |
| 3 | 0 |
| 4 | -3 |
| 5 | 96 |
| 6 | -621 |
| 7 | 0 |
| 8 | -17703 |
| 9 | 1161216 |
| 10 | -13961241 |
| 11 | 0 |
| 12 | -1125897003 |
| 13 | 111588212736 |
| 14 | -1962807307461 |
| 15 | 0 |
| 16 | -313129783869903 |
| 17 | 41521527606214656 |
| 18 | -961674168773599281 |
| 19 | 0 |
| 20 | -255030903352871048403 |
| 21 | 42355944224989145726976 |
| 22 | -1217055203596100484316701 |
| 23 | 0 |
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