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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 0 |
| 3 | -3 |
| 4 | 0 |
| 5 | -10 |
| 6 | 90 |
| 7 | -112 |
| 8 | 1680 |
| 9 | -10008 |
| 10 | 52920 |
| 11 | -503096 |
| 12 | 3750120 |
| 13 | -32707376 |
| 14 | 317212896 |
| 15 | -3115701240 |
| 16 | 33444028800 |
| 17 | -378122087104 |
| 18 | 4501793066688 |
| 19 | -56612612281984 |
| 20 | 746976298243200 |
| 21 | -10328059310335872 |
| 22 | 149410872069250176 |
| 23 | -2255298661460780288 |
| 24 | 35481940129572393600 |
[1,0,0,-3,0,-10,90,-112,1680,-10008,52920,-503096, 3750120,-32707376,317212896,-3115701240, 33444028800,-378122087104,4501793066688, -56612612281984,746976298243200, -10328059310335872,149410872069250176, -2255298661460780288,35481940129572393600] |