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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | -2 |
| 2 | 2 |
| 3 | -1 |
| 4 | 1 |
| 5 | -4 |
| 6 | 4 |
| 7 | 13 |
| 8 | -13 |
| 9 | -142 |
| 10 | 142 |
| 11 | 1931 |
| 12 | -1931 |
| 13 | -36296 |
| 14 | 36296 |
| 15 | 893273 |
| 16 | -893273 |
| 17 | -27927346 |
| 18 | 27927346 |
| 19 | 1081725559 |
| 20 | -1081725559 |
| 21 | -50861556172 |
| 22 | 50861556172 |
| 23 | 2854289486309 |
| 24 | -2854289486309 |
| 25 | -188475382997654 |
| 26 | 188475382997654 |
| 27 | 14467150771771043 |
| 28 | -14467150771771043 |
[1,-2,2,-1,1,-4,4,13,-13,-142,142,1931,-1931, -36296,36296,893273,-893273,-27927346,27927346, 1081725559,-1081725559,-50861556172,50861556172, 2854289486309,-2854289486309,-188475382997654, 188475382997654,14467150771771043, -14467150771771043] |