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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | -1 |
| 2 | 3 |
| 3 | -5 |
| 4 | 17 |
| 5 | -31 |
| 6 | 119 |
| 7 | -211 |
| 8 | 937 |
| 9 | -1483 |
| 10 | 8015 |
| 11 | -10187 |
| 12 | 73369 |
| 13 | -62193 |
| 14 | 713907 |
| 15 | -234857 |
| 16 | 7358657 |
| 17 | 1881661 |
| 18 | 80117735 |
| 19 | 69295469 |
| 20 | 917837521 |
| 21 | 1334044075 |
| 22 | 11006114883 |
| 23 | 21830065899 |
| 24 | 137275956089 |
| 25 | 333858963899 |
| 26 | 1769128762419 |
| 27 | 4940496514271 |
| 28 | 23409778504937 |
[1,-1,3,-5,17,-31,119,-211,937,-1483,8015,-10187, 73369,-62193,713907,-234857,7358657,1881661, 80117735,69295469,917837521,1334044075, 11006114883,21830065899,137275956089,333858963899, 1769128762419,4940496514271,23409778504937] |