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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 4 |
| 3 | -6 |
| 4 | 43 |
| 5 | -170 |
| 6 | 1204 |
| 7 | -7917 |
| 8 | 65853 |
| 9 | -583956 |
| 10 | 5887014 |
| 11 | -64564335 |
| 12 | 775951059 |
| 13 | -10081978062 |
| 14 | 141184231920 |
| 15 | -2117576980365 |
| 16 | 33882606676089 |
| 17 | -575996551450984 |
| 18 | 10367999657321034 |
| 19 | -196991613574996347 |
[1,0,4,-6,43,-170,1204,-7917,65853,-583956, 5887014,-64564335,775951059,-10081978062, 141184231920,-2117576980365,33882606676089, -575996551450984,10367999657321034, -196991613574996347] |