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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 12 |
| 5 | -60 |
| 6 | 210 |
| 7 | -1260 |
| 8 | 11760 |
| 9 | -114912 |
| 10 | 1111560 |
| 11 | -11676720 |
| 12 | 138570696 |
| 13 | -1799232864 |
| 14 | 25005472128 |
| 15 | -371229549600 |
| 16 | 5885388887040 |
| 17 | -99270313446784 |
| 18 | 1773606197591232 |
| 19 | -33452898176207232 |
| 20 | 664355584657373312 |
[1,0,0,0,12,-60,210,-1260,11760,-114912,1111560, -11676720,138570696,-1799232864,25005472128, -371229549600,5885388887040,-99270313446784, 1773606197591232,-33452898176207232, 664355584657373312] |