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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | -2 |
| 2 | 1 |
| 3 | -1 |
| 4 | -9 |
| 5 | -59 |
| 6 | -474 |
| 7 | -4560 |
| 8 | -50364 |
| 9 | -625385 |
| 10 | -8622658 |
| 11 | -130751886 |
| 12 | -2163331779 |
| 13 | -38793751015 |
| 14 | -749691306018 |
| 15 | -15535914341831 |
| 16 | -343749787006758 |
| 17 | -8089725377931547 |
| 18 | -201801866906374263 |
| 19 | -5319643146604299835 |
| 20 | -147774950436327236681 |
[1,-2,1,-1,-9,-59,-474,-4560,-50364,-625385, -8622658,-130751886,-2163331779,-38793751015, -749691306018,-15535914341831,-343749787006758, -8089725377931547,-201801866906374263, -5319643146604299835,-147774950436327236681] |