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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | -3 |
| 5 | 40 |
| 6 | -250 |
| 7 | 1008 |
| 8 | -6307 |
| 9 | 77040 |
| 10 | -742524 |
| 11 | 5642560 |
| 12 | -56921887 |
| 13 | 809088696 |
| 14 | -10450329838 |
| 15 | 122609052720 |
| 16 | -1712600698983 |
| 17 | 28629942196960 |
| 18 | -466274068556152 |
| 19 | 7411488125575680 |
| 20 | -130844029905109723 |
[1,0,0,0,-3,40,-250,1008,-6307,77040,-742524, 5642560,-56921887,809088696,-10450329838, 122609052720,-1712600698983,28629942196960, -466274068556152,7411488125575680, -130844029905109723] |