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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | -1 |
| 3 | 1 |
| 4 | -1 |
| 5 | 1 |
| 6 | -691 |
| 7 | 1 |
| 8 | -3617 |
| 9 | 43867 |
| 10 | -174611 |
| 11 | 77683 |
| 12 | -236364091 |
| 13 | 657931 |
| 14 | -3392780147 |
| 15 | 1723168255201 |
| 16 | -7709321041217 |
| 17 | 151628697551 |
| 18 | -26315271553053477373 |
| 19 | 154210205991661 |
| 20 | -261082718496449122051 |
| 21 | 1520097643918070802691 |
| 22 | -2530297234481911294093 |
[1,-1,1,-1,1,-691,1,-3617,43867,-174611,77683, -236364091,657931,-3392780147,1723168255201, -7709321041217,151628697551,-26315271553053477373, 154210205991661,-261082718496449122051, 1520097643918070802691,-2530297234481911294093] |