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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | -1 |
| 3 | 1 |
| 4 | 1 |
| 5 | -7 |
| 6 | 8 |
| 7 | -1 |
| 8 | -57 |
| 9 | 391 |
| 10 | -455 |
| 11 | -2729 |
| 12 | 22352 |
| 13 | -175111 |
| 14 | 47767 |
| 15 | 8888873 |
| 16 | -69739671 |
| 17 | 565353361 |
| 18 | 3385862936 |
| 19 | -195345149609 |
| 20 | 1747973613295 |
| 21 | -4686154246801 |
| 22 | -632038062613231 |
| 23 | 34045765616463119 |
| 24 | -319807929289790304 |
| 25 | -11453004955077020783 |
[0,1,-1,1,1,-7,8,-1,-57,391,-455,-2729,22352, -175111,47767,8888873,-69739671,565353361, 3385862936,-195345149609,1747973613295, -4686154246801,-632038062613231,34045765616463119, -319807929289790304,-11453004955077020783] |