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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | -1 |
| 2 | 1 |
| 3 | 0 |
| 4 | -2 |
| 5 | 1 |
| 6 | 1 |
| 7 | 0 |
| 8 | -3 |
| 9 | 1 |
| 10 | 1 |
| 11 | 4 |
| 12 | 0 |
| 13 | -4 |
| 14 | 1 |
| 15 | -2 |
| 16 | 5 |
| 17 | 10 |
| 18 | 0 |
| 19 | -5 |
| 20 | 1 |
| 21 | -9 |
| 22 | -12 |
| 23 | 15 |
| 24 | 20 |
| 25 | 0 |
| 26 | -6 |
| 27 | 1 |
| 28 | -9 |
| 29 | -63 |
| 30 | -42 |
| 31 | 35 |
| 32 | 35 |
| 33 | 0 |
| 34 | -7 |
| 35 | 1 |
| 36 | 50 |
| 37 | -72 |
| 38 | -252 |
| 39 | -112 |
| 40 | 70 |
| 41 | 56 |
| 42 | 0 |
| 43 | -8 |
| 44 | 1 |
| 45 | 267 |
| 46 | 450 |
| 47 | -324 |
| 48 | -756 |
| 49 | -252 |
| 50 | 126 |
| 51 | 84 |
| 52 | 0 |
| 53 | -9 |
| 54 | 1 |
| 55 | 413 |
| 56 | 2670 |
| 57 | 2250 |
| 58 | -1080 |
| 59 | -1890 |
| 60 | -504 |
| 61 | 210 |
| 62 | 120 |
| 63 | 0 |
| 64 | -10 |
| 65 | 1 |
[1,-1,1,0,-2,1,1,0,-3,1,1,4,0,-4,1,-2,5,10,0,-5,1, -9,-12,15,20,0,-6,1,-9,-63,-42,35,35,0,-7,1,50, -72,-252,-112,70,56,0,-8,1,267,450,-324,-756,-252, 126,84,0,-9,1,413,2670,2250,-1080,-1890,-504,210, 120,0,-10,1] |