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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | -15 |
| 3 | 125 |
| 4 | -935 |
| 5 | 6096 |
| 6 | -38340 |
| 7 | 240864 |
| 8 | -1497584 |
| 9 | 8611328 |
| 10 | -49201152 |
| 11 | 277473280 |
| 12 | -1541996288 |
| 13 | 7852493824 |
| 14 | -39972516864 |
| 15 | 195624648704 |
| 16 | -789661486080 |
| 17 | 3052709008384 |
| 18 | -9659706075392 |
| 19 | 30089357409792 |
| 20 | -63825905935360 |
| 21 | 63965499203712 |
| 22 | -8296932715920 |
| 23 | -1139418909751008 |
[1,-15,125,-935,6096,-38340,240864,-1497584, 8611328,-49201152,277473280,-1541996288, 7852493824,-39972516864,195624648704, -789661486080,3052709008384,-9659706075392, 30089357409792,-63825905935360,63965499203712, -8296932715920,-1139418909751008] |