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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | -1 |
| 3 | 2 |
| 4 | -2 |
| 5 | 8 |
| 6 | 16 |
| 7 | -96 |
| 8 | 96 |
| 9 | -192 |
| 10 | -768 |
| 11 | 7680 |
| 12 | 15360 |
| 13 | -184320 |
| 14 | -1105920 |
| 15 | -8847360 |
| 16 | 8847360 |
| 17 | -141557760 |
| 18 | -283115520 |
| 19 | 5096079360 |
| 20 | 20384317440 |
| 21 | 244611809280 |
| 22 | 2446118092800 |
| 23 | -53814598041600 |
| 24 | -107629196083200 |
| 25 | 430516784332800 |
| 26 | 5166201411993600 |
| 27 | -10332402823987200 |
[1,-1,2,-2,8,16,-96,96,-192,-768,7680,15360, -184320,-1105920,-8847360,8847360,-141557760, -283115520,5096079360,20384317440,244611809280, 2446118092800,-53814598041600,-107629196083200, 430516784332800,5166201411993600, -10332402823987200] |