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| n | a(n) |
|---|---|
| 0 | -1 |
| 1 | 1 |
| 2 | -1 |
| 3 | 1 |
| 4 | -1 |
| 5 | 1 |
| 6 | 2 |
| 7 | -1 |
| 8 | 2 |
| 9 | -1 |
| 10 | 6 |
| 11 | -4 |
| 12 | 9 |
| 13 | -6 |
| 14 | 1 |
| 15 | 24 |
| 16 | -121 |
| 17 | 264 |
| 18 | -166 |
| 19 | 24 |
| 20 | -1 |
| 21 | 120 |
| 22 | -44616 |
| 23 | 93340 |
| 24 | -52950 |
| 25 | 4345 |
| 26 | -120 |
| 27 | 1 |
| 28 | 720 |
| 29 | -296321796 |
| 30 | 605003244 |
| 31 | -321204409 |
| 32 | 12686988 |
| 33 | -164746 |
| 34 | 720 |
| 35 | -1 |
| 36 | 5040 |
| 37 | -49349521382400 |
| 38 | 99624831647040 |
| 39 | -51206316902496 |
[-1,1,-1,1,-1,1,2,-1,2,-1,6,-4,9,-6,1,24,-121,264, -166,24,-1,120,-44616,93340,-52950,4345,-120,1, 720,-296321796,605003244,-321204409,12686988, -164746,720,-1,5040,-49349521382400, 99624831647040,-51206316902496] |