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| n | a(n) |
|---|---|
| 0 | 2 |
| 1 | 1 |
| 2 | 1 |
| 3 | -3 |
| 4 | 7 |
| 5 | 15 |
| 6 | -39 |
| 7 | -307 |
| 8 | 917 |
| 9 | 2540 |
| 10 | -16939 |
| 11 | -25016 |
| 12 | 441962 |
| 13 | -498346 |
| 14 | -10210949 |
| 15 | 42714405 |
| 16 | 195220459 |
| 17 | -2142879945 |
| 18 | 532985665 |
| 19 | 83535107090 |
| 20 | -365902332521 |
| 21 | -2233273290797 |
| 22 | 28143121253695 |
| 23 | -20874136499710 |
| 24 | -1436795595314700 |
| 25 | 8862053852144592 |
| 26 | 38496064560804831 |
[2,1,1,-3,7,15,-39,-307,917,2540,-16939,-25016, 441962,-498346,-10210949,42714405,195220459, -2142879945,532985665,83535107090,-365902332521, -2233273290797,28143121253695,-20874136499710, -1436795595314700,8862053852144592, 38496064560804831] |