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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | -4 |
| 3 | 23 |
| 4 | -150 |
| 5 | 1054 |
| 6 | -7761 |
| 7 | 58998 |
| 8 | -459085 |
| 9 | 3636389 |
| 10 | -29209558 |
| 11 | 237295537 |
| 12 | -1945823646 |
| 13 | 16081045446 |
| 14 | -133787515943 |
| 15 | 1119454523221 |
| 16 | -9413778489629 |
| 17 | 79510460561765 |
| 18 | -674169212593940 |
| 19 | 5736078315701995 |
| 20 | -48956250060321142 |
| 21 | 419002149097227663 |
[1,1,-4,23,-150,1054,-7761,58998,-459085,3636389, -29209558,237295537,-1945823646,16081045446, -133787515943,1119454523221,-9413778489629, 79510460561765,-674169212593940,5736078315701995, -48956250060321142,419002149097227663] |