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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | -1 |
| 2 | 1 |
| 3 | -1 |
| 4 | 1 |
| 5 | 1 |
| 6 | -1 |
| 7 | 1 |
| 8 | 2 |
| 9 | 1 |
| 10 | -1 |
| 11 | 1 |
| 12 | 3 |
| 13 | 3 |
| 14 | 1 |
| 15 | -1 |
| 16 | 1 |
| 17 | 4 |
| 18 | 6 |
| 19 | 4 |
| 20 | 1 |
| 21 | -1 |
| 22 | 1 |
| 23 | 5 |
| 24 | 10 |
| 25 | 10 |
| 26 | 5 |
| 27 | 1 |
| 28 | -1 |
| 29 | 1 |
| 30 | 6 |
| 31 | 15 |
| 32 | 20 |
| 33 | 15 |
| 34 | 6 |
| 35 | 1 |
| 36 | -1 |
| 37 | 1 |
| 38 | 7 |
| 39 | 21 |
| 40 | 35 |
| 41 | 35 |
| 42 | 21 |
| 43 | 7 |
| 44 | 1 |
| 45 | -1 |
| 46 | 1 |
| 47 | 8 |
| 48 | 28 |
| 49 | 56 |
| 50 | 70 |
| 51 | 56 |
| 52 | 28 |
| 53 | 8 |
| 54 | 1 |
| 55 | -1 |
| 56 | 1 |
| 57 | 9 |
| 58 | 36 |
| 59 | 84 |
| 60 | 126 |
| 61 | 126 |
| 62 | 84 |
| 63 | 36 |
| 64 | 9 |
| 65 | 1 |
| 66 | -1 |
| 67 | 1 |
| 68 | 10 |
| 69 | 45 |
| 70 | 120 |
| 71 | 210 |
| 72 | 252 |
| 73 | 210 |
| 74 | 120 |
| 75 | 45 |
| 76 | 10 |
| 77 | 1 |
[1,-1,1,-1,1,1,-1,1,2,1,-1,1,3,3,1,-1,1,4,6,4,1, -1,1,5,10,10,5,1,-1,1,6,15,20,15,6,1,-1,1,7,21,35, 35,21,7,1,-1,1,8,28,56,70,56,28,8,1,-1,1,9,36,84, 126,126,84,36,9,1,-1,1,10,45,120,210,252,210,120, 45,10,1] |