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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | -1 |
| 5 | 2 |
| 6 | 1 |
| 7 | -1 |
| 8 | 2 |
| 9 | 6 |
| 10 | 1 |
| 11 | -1 |
| 12 | 3 |
| 13 | -12 |
| 14 | 24 |
| 15 | 1 |
| 16 | -1 |
| 17 | 4 |
| 18 | -36 |
| 19 | 288 |
| 20 | 120 |
| 21 | 1 |
| 22 | -1 |
| 23 | 5 |
| 24 | -80 |
| 25 | 2160 |
| 26 | -34560 |
| 27 | 720 |
| 28 | 1 |
| 29 | -1 |
| 30 | 6 |
| 31 | -150 |
| 32 | 9600 |
| 33 | -777600 |
| 34 | 24883200 |
| 35 | 5040 |
| 36 | 1 |
| 37 | -1 |
| 38 | 7 |
| 39 | -252 |
| 40 | 31500 |
| 41 | -8064000 |
| 42 | 1959552000 |
| 43 | -125411328000 |
| 44 | 40320 |
| 45 | 1 |
| 46 | -1 |
| 47 | 8 |
| 48 | -392 |
| 49 | 84672 |
| 50 | -52920000 |
[1,1,1,1,-1,2,1,-1,2,6,1,-1,3,-12,24,1,-1,4,-36, 288,120,1,-1,5,-80,2160,-34560,720,1,-1,6,-150, 9600,-777600,24883200,5040,1,-1,7,-252,31500, -8064000,1959552000,-125411328000,40320,1,-1,8, -392,84672,-52920000] |