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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 1 |
| 3 | -1 |
| 4 | -26 |
| 5 | 39 |
| 6 | 3666 |
| 7 | -7400 |
| 8 | -1488416 |
| 9 | 3802113 |
| 10 | 1322570530 |
| 11 | -4095154284 |
| 12 | -2187371499312 |
| 13 | 7964242253473 |
| 14 | 6052757424558586 |
| 15 | -25343867475914910 |
| 16 | -25988018018090461664 |
| 17 | 123032891453320498449 |
| 18 | 163684285184147641156098 |
| 19 | -864557405968781387651984 |
| 20 | -1448111703094244548802632160 |
[0,1,1,-1,-26,39,3666,-7400,-1488416,3802113, 1322570530,-4095154284,-2187371499312, 7964242253473,6052757424558586,-25343867475914910, -25988018018090461664,123032891453320498449, 163684285184147641156098, -864557405968781387651984, -1448111703094244548802632160] |