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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | -1 |
| 3 | 1 |
| 4 | -2 |
| 5 | 1 |
| 6 | 1 |
| 7 | -3 |
| 8 | 5 |
| 9 | -3 |
| 10 | 1 |
| 11 | -4 |
| 12 | 14 |
| 13 | -28 |
| 14 | 17 |
| 15 | 1 |
| 16 | -5 |
| 17 | 30 |
| 18 | -126 |
| 19 | 255 |
| 20 | -155 |
| 21 | 1 |
| 22 | -6 |
| 23 | 55 |
| 24 | -396 |
| 25 | 1683 |
| 26 | -3410 |
| 27 | 2073 |
| 28 | 1 |
| 29 | -7 |
| 30 | 91 |
| 31 | -1001 |
| 32 | 7293 |
| 33 | -31031 |
| 34 | 62881 |
| 35 | -38227 |
| 36 | 1 |
| 37 | -8 |
| 38 | 140 |
| 39 | -2184 |
| 40 | 24310 |
| 41 | -177320 |
| 42 | 754572 |
| 43 | -1529080 |
| 44 | 929569 |
| 45 | 1 |
| 46 | -9 |
| 47 | 204 |
| 48 | -4284 |
| 49 | 67626 |
| 50 | -753610 |
| 51 | 5497596 |
| 52 | -23394924 |
| 53 | 47408019 |
[1,1,-1,1,-2,1,1,-3,5,-3,1,-4,14,-28,17,1,-5,30, -126,255,-155,1,-6,55,-396,1683,-3410,2073,1,-7, 91,-1001,7293,-31031,62881,-38227,1,-8,140,-2184, 24310,-177320,754572,-1529080,929569,1,-9,204, -4284,67626,-753610,5497596,-23394924,47408019] |