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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 3 |
| 5 | -30 |
| 6 | 180 |
| 7 | -945 |
| 8 | 7665 |
| 9 | -94500 |
| 10 | 1124550 |
| 11 | -12525975 |
| 12 | 156808575 |
| 13 | -2347294950 |
| 14 | 37345908600 |
| 15 | -602685208125 |
| 16 | 10429905110625 |
| 17 | -198454585329000 |
| 18 | 3981241066052250 |
| 19 | -82461126798925875 |
[1,0,0,0,3,-30,180,-945,7665,-94500,1124550, -12525975,156808575,-2347294950,37345908600, -602685208125,10429905110625,-198454585329000, 3981241066052250,-82461126798925875] |