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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 12 |
| 5 | -60 |
| 6 | 450 |
| 7 | -2940 |
| 8 | 24080 |
| 9 | -215712 |
| 10 | 2245320 |
| 11 | -25552560 |
| 12 | 318861576 |
| 13 | -4280157024 |
| 14 | 61675886272 |
| 15 | -948295464480 |
| 16 | 15514105784320 |
| 17 | -269094947517824 |
| 18 | 4934169151898304 |
| 19 | -95367032452388736 |
| 20 | 1937946889478705792 |
[1,0,0,0,12,-60,450,-2940,24080,-215712,2245320, -25552560,318861576,-4280157024,61675886272, -948295464480,15514105784320,-269094947517824, 4934169151898304,-95367032452388736, 1937946889478705792] |