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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | -1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 0 |
| 6 | 1 |
| 7 | 1 |
| 8 | 1 |
| 9 | 3 |
| 10 | 4 |
| 11 | -5 |
| 12 | 1 |
| 13 | -7 |
| 14 | 9 |
| 15 | 8 |
| 16 | 25 |
| 17 | -23 |
| 18 | 49 |
| 19 | 87 |
| 20 | 16 |
| 21 | 295 |
| 22 | 529 |
| 23 | -903 |
| 24 | 841 |
| 25 | -1256 |
| 26 | 3481 |
| 27 | -1495 |
| 28 | 16641 |
| 29 | -44341 |
| 30 | 98596 |
| 31 | 217651 |
| 32 | 4225 |
| 33 | 1058961 |
| 34 | 2337841 |
| 35 | -5106896 |
| 36 | 13608721 |
| 37 | 5415345 |
| 38 | 67387681 |
| 39 | -173830481 |
| 40 | 264517696 |
| 41 | -2288275633 |
| 42 | 6941055969 |
[0,-1,1,1,1,0,1,1,1,3,4,-5,1,-7,9,8,25,-23,49,87, 16,295,529,-903,841,-1256,3481,-1495,16641,-44341, 98596,217651,4225,1058961,2337841,-5106896, 13608721,5415345,67387681,-173830481,264517696, -2288275633,6941055969] |