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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | -3 |
| 2 | 9 |
| 3 | -18 |
| 4 | -57 |
| 5 | 942 |
| 6 | -4299 |
| 7 | -33078 |
| 8 | 786267 |
| 9 | -4357818 |
| 10 | -84919647 |
| 11 | 2153185746 |
| 12 | -9754462833 |
| 13 | -539983739298 |
| 14 | 13389257569005 |
| 15 | -13826647549926 |
| 16 | -6661768436593725 |
| 17 | 153336015047780790 |
| 18 | 938088731006163417 |
| 19 | -139051687661849130654 |
| 20 | 2787586449012275332023 |
[1,-3,9,-18,-57,942,-4299,-33078,786267,-4357818, -84919647,2153185746,-9754462833,-539983739298, 13389257569005,-13826647549926,-6661768436593725, 153336015047780790,938088731006163417, -139051687661849130654,2787586449012275332023] |