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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | -1 |
| 3 | 3 |
| 4 | -5 |
| 5 | -10 |
| 6 | 146 |
| 7 | -756 |
| 8 | 1086 |
| 9 | 23400 |
| 10 | -300066 |
| 11 | 1855590 |
| 12 | 341826 |
| 13 | -165915828 |
| 14 | 2158958556 |
| 15 | -10006622640 |
| 16 | -172337345496 |
| 17 | 4941605486016 |
| 18 | -64365944851512 |
| 19 | 339328464492456 |
| 20 | 5510899593823176 |
| 21 | -157099566384759600 |
| 22 | 1059259019507498160 |
| 23 | 41957473280879898720 |
[1,0,-1,3,-5,-10,146,-756,1086,23400,-300066, 1855590,341826,-165915828,2158958556,-10006622640, -172337345496,4941605486016,-64365944851512, 339328464492456,5510899593823176, -157099566384759600,1059259019507498160, 41957473280879898720] |