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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | -1 |
| 3 | 1 |
| 4 | -1 |
| 5 | 0 |
| 6 | 4 |
| 7 | -16 |
| 8 | 46 |
| 9 | -111 |
| 10 | 228 |
| 11 | -379 |
| 12 | 389 |
| 13 | 393 |
| 14 | -3810 |
| 15 | 14169 |
| 16 | -39735 |
| 17 | 91861 |
| 18 | -172623 |
| 19 | 225378 |
| 20 | 10246 |
| 21 | -1347935 |
| 22 | 5843671 |
| 23 | -17779693 |
| 24 | 43942706 |
| 25 | -89033228 |
| 26 | 133666868 |
| 27 | -64088688 |
| 28 | -508956437 |
| 29 | 2636138606 |
| 30 | -8664888857 |
| 31 | 22760994036 |
| 32 | -49429259575 |
[1,-1,1,-1,0,4,-16,46,-111,228,-379,389,393,-3810, 14169,-39735,91861,-172623,225378,10246,-1347935, 5843671,-17779693,43942706,-89033228,133666868, -64088688,-508956437,2636138606,-8664888857, 22760994036,-49429259575] |