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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | -1 |
| 3 | 7 |
| 4 | -43 |
| 5 | 221 |
| 6 | -341 |
| 7 | -15980 |
| 8 | 370761 |
| 9 | -5688125 |
| 10 | 62689871 |
| 11 | -197586839 |
| 12 | -14973562979 |
| 13 | 585250669316 |
| 14 | -14306382821485 |
| 15 | 240985102271971 |
| 16 | -1121421968408303 |
| 17 | -122020498882279931 |
| 18 | 6674724196051810807 |
| 19 | -223424819176020519168 |
| 20 | 5051515662105879438501 |
[1,0,-1,7,-43,221,-341,-15980,370761,-5688125, 62689871,-197586839,-14973562979,585250669316, -14306382821485,240985102271971,-1121421968408303, -122020498882279931,6674724196051810807, -223424819176020519168,5051515662105879438501] |