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| n | a(n) |
|---|---|
| 1 | -1 |
| 2 | 0 |
| 3 | -1 |
| 4 | 2 |
| 5 | 0 |
| 6 | -1 |
| 7 | -6 |
| 8 | 6 |
| 9 | 0 |
| 10 | -1 |
| 11 | 14 |
| 12 | -24 |
| 13 | 12 |
| 14 | 0 |
| 15 | -1 |
| 16 | -30 |
| 17 | 70 |
| 18 | -60 |
| 19 | 20 |
| 20 | 0 |
| 21 | -1 |
| 22 | 62 |
| 23 | -180 |
| 24 | 210 |
| 25 | -120 |
| 26 | 30 |
| 27 | 0 |
| 28 | -1 |
| 29 | -126 |
| 30 | 434 |
| 31 | -630 |
| 32 | 490 |
| 33 | -210 |
| 34 | 42 |
| 35 | 0 |
| 36 | -1 |
| 37 | 254 |
| 38 | -1008 |
| 39 | 1736 |
| 40 | -1680 |
| 41 | 980 |
| 42 | -336 |
| 43 | 56 |
| 44 | 0 |
| 45 | -1 |
| 46 | -510 |
| 47 | 2286 |
| 48 | -4536 |
| 49 | 5208 |
| 50 | -3780 |
| 51 | 1764 |
| 52 | -504 |
| 53 | 72 |
| 54 | 0 |
| 55 | -1 |
| 56 | 1022 |
| 57 | -5100 |
| 58 | 11430 |
| 59 | -15120 |
| 60 | 13020 |
| 61 | -7560 |
| 62 | 2940 |
| 63 | -720 |
| 64 | 90 |
| 65 | 0 |
| 66 | -1 |
[-1,0,-1,2,0,-1,-6,6,0,-1,14,-24,12,0,-1,-30,70, -60,20,0,-1,62,-180,210,-120,30,0,-1,-126,434, -630,490,-210,42,0,-1,254,-1008,1736,-1680,980, -336,56,0,-1,-510,2286,-4536,5208,-3780,1764,-504, 72,0,-1,1022,-5100,11430,-15120,13020,-7560,2940, -720,90,0,-1] |