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| n | a(n) |
|---|---|
| 0 | -1 |
| 1 | -1 |
| 2 | 3 |
| 3 | -1 |
| 4 | 10 |
| 5 | -15 |
| 6 | -1 |
| 7 | 15 |
| 8 | 10 |
| 9 | -105 |
| 10 | 105 |
| 11 | -1 |
| 12 | 21 |
| 13 | 35 |
| 14 | -210 |
| 15 | -280 |
| 16 | 1260 |
| 17 | -945 |
| 18 | -1 |
| 19 | 28 |
| 20 | 56 |
| 21 | 35 |
| 22 | -378 |
| 23 | -1260 |
| 24 | -280 |
| 25 | 3150 |
| 26 | 6300 |
| 27 | -17325 |
| 28 | 10395 |
| 29 | -1 |
| 30 | 36 |
| 31 | 84 |
| 32 | 126 |
| 33 | -630 |
| 34 | -2520 |
| 35 | -1575 |
| 36 | -2100 |
| 37 | 6930 |
| 38 | 34650 |
| 39 | 15400 |
| 40 | -51975 |
| 41 | -138600 |
| 42 | 270270 |
| 43 | -135135 |
| 44 | -1 |
| 45 | 45 |
| 46 | 120 |
| 47 | 210 |
| 48 | 126 |
| 49 | -990 |
| 50 | -4620 |
| 51 | -6930 |
| 52 | -4620 |
| 53 | -5775 |
[-1,-1,3,-1,10,-15,-1,15,10,-105,105,-1,21,35, -210,-280,1260,-945,-1,28,56,35,-378,-1260,-280, 3150,6300,-17325,10395,-1,36,84,126,-630,-2520, -1575,-2100,6930,34650,15400,-51975,-138600, 270270,-135135,-1,45,120,210,126,-990,-4620,-6930, -4620,-5775] |