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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 3 |
| 6 | 2 |
| 7 | -7 |
| 8 | -13 |
| 9 | -25 |
| 10 | 3 |
| 11 | -173 |
| 12 | -332 |
| 13 | 1237 |
| 14 | 2149 |
| 15 | 12969 |
| 16 | -34411 |
| 17 | 212159 |
| 18 | 729350 |
| 19 | -5405899 |
| 20 | 2412231 |
| 21 | -129451889 |
| 22 | 951511591 |
| 23 | -6624402137 |
| 24 | -19829335448 |
| 25 | 484740289833 |
| 26 | -2548271136343 |
| 27 | 27842908929425 |
| 28 | -353158277960887 |
| 29 | 5055074341844027 |
[0,1,1,1,1,3,2,-7,-13,-25,3,-173,-332,1237,2149, 12969,-34411,212159,729350,-5405899,2412231, -129451889,951511591,-6624402137,-19829335448, 484740289833,-2548271136343,27842908929425, -353158277960887,5055074341844027] |