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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | -3 |
| 3 | 25 |
| 4 | -335 |
| 5 | 6177 |
| 6 | -144947 |
| 7 | 4128937 |
| 8 | -138327615 |
| 9 | 5327738497 |
| 10 | -231899041475 |
| 11 | 11255588133945 |
| 12 | -602683483719503 |
| 13 | 35288931375293857 |
| 14 | -2242963870471014963 |
| 15 | 153791777744471484745 |
| 16 | -11314787069889491407103 |
| 17 | 889087243145447511507969 |
| 18 | -74312052321224600661026051 |
[1,1,-3,25,-335,6177,-144947,4128937,-138327615, 5327738497,-231899041475,11255588133945, -602683483719503,35288931375293857, -2242963870471014963,153791777744471484745, -11314787069889491407103,889087243145447511507969, -74312052321224600661026051] |