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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 0 |
| 3 | 3 |
| 4 | -11 |
| 5 | 25 |
| 6 | -59 |
| 7 | 721 |
| 8 | -10919 |
| 9 | 60481 |
| 10 | -15119 |
| 11 | 3628801 |
| 12 | -93471839 |
| 13 | 479001601 |
| 14 | -8648639 |
| 15 | 134399865601 |
| 16 | -2833553923199 |
| 17 | 20922789888001 |
| 18 | -174888473759999 |
| 19 | 6402373705728001 |
| 20 | -228084898487846399 |
| 21 | 3652732042831872001 |
| 22 | -14079294028799 |
[1,0,3,-11,25,-59,721,-10919,60481,-15119,3628801, -93471839,479001601,-8648639,134399865601, -2833553923199,20922789888001,-174888473759999, 6402373705728001,-228084898487846399, 3652732042831872001,-14079294028799] |