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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | -96 |
| 2 | 3168 |
| 3 | -34944 |
| 4 | -107808 |
| 5 | 1955520 |
| 6 | 16829568 |
| 7 | 76708608 |
| 8 | 258593760 |
| 9 | 715480608 |
| 10 | 1729546560 |
| 11 | 3771497088 |
| 12 | 7581237888 |
| 13 | 14296261056 |
| 14 | 25520442624 |
| 15 | 43590539520 |
| 16 | 71582414304 |
| 17 | 113752634688 |
| 18 | 175604039136 |
| 19 | 264097115520 |
| 20 | 388619703360 |
| 21 | 559658001408 |
| 22 | 792716685696 |
[1,-96,3168,-34944,-107808,1955520,16829568, 76708608,258593760,715480608,1729546560, 3771497088,7581237888,14296261056,25520442624, 43590539520,71582414304,113752634688,175604039136, 264097115520,388619703360,559658001408, 792716685696] |