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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | -1 |
| 2 | -1 |
| 3 | -13 |
| 4 | -367 |
| 5 | -18549 |
| 6 | -1465953 |
| 7 | -166262441 |
| 8 | -25526158559 |
| 9 | -5088504559209 |
| 10 | -1277203721141441 |
| 11 | -394351281523218693 |
| 12 | -147069662568684159055 |
| 13 | -65255038602423680990301 |
| 14 | -33992871584988519888865825 |
| 15 | -20539580068386370855911967393 |
| 16 | -14240009948449682448965044873663 |
| 17 | -11224227759618581623496389602591953 |
| 18 | -9984932631658989030110444663072663937 |
| 19 | -9963529315662216629464111409263738683133 |
[1,-1,-1,-13,-367,-18549,-1465953,-166262441, -25526158559,-5088504559209,-1277203721141441, -394351281523218693,-147069662568684159055, -65255038602423680990301, -33992871584988519888865825, -20539580068386370855911967393, -14240009948449682448965044873663, -11224227759618581623496389602591953, -9984932631658989030110444663072663937, -9963529315662216629464111409263738683133] |