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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | -1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 0 |
| 6 | 0 |
| 7 | 2 |
| 8 | 3 |
| 9 | 1 |
| 10 | 2 |
| 11 | 11 |
| 12 | 17 |
| 13 | 12 |
| 14 | 25 |
| 15 | 81 |
| 16 | 127 |
| 17 | 134 |
| 18 | 276 |
| 19 | 696 |
| 20 | 1118 |
| 21 | 1492 |
| 22 | 3005 |
| 23 | 6607 |
| 24 | 10935 |
| 25 | 16766 |
| 26 | 33047 |
| 27 | 67249 |
| 28 | 114611 |
| 29 | 190706 |
| 30 | 369424 |
| 31 | 719956 |
| 32 | 1258251 |
| 33 | 2196855 |
| 34 | 4201958 |
| 35 | 8000409 |
| 36 | 14263679 |
| 37 | 25620508 |
| 38 | 48585009 |
| 39 | 91421253 |
| 40 | 165467590 |
[1,-1,1,1,0,0,2,3,1,2,11,17,12,25,81,127,134,276, 696,1118,1492,3005,6607,10935,16766,33047,67249, 114611,190706,369424,719956,1258251,2196855, 4201958,8000409,14263679,25620508,48585009, 91421253,165467590] |