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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | -2 |
| 4 | 4 |
| 5 | -8 |
| 6 | 15 |
| 7 | -25 |
| 8 | 35 |
| 9 | -35 |
| 10 | 0 |
| 11 | 126 |
| 12 | -462 |
| 13 | 1253 |
| 14 | -2989 |
| 15 | 6615 |
| 16 | -13867 |
| 17 | 27734 |
| 18 | -52921 |
| 19 | 95863 |
| 20 | -163115 |
| 21 | 255493 |
| 22 | -352716 |
| 23 | 379050 |
| 24 | -134596 |
| 25 | -828875 |
| 26 | 3407821 |
| 27 | -9217717 |
| 28 | 20837509 |
| 29 | -41675018 |
| 30 | 74480265 |
| 31 | -116145145 |
| 32 | 143502875 |
| 33 | -78990635 |
| 34 | -286097760 |
| 35 | 1453179125 |
[1,1,-2,4,-8,15,-25,35,-35,0,126,-462,1253,-2989, 6615,-13867,27734,-52921,95863,-163115,255493, -352716,379050,-134596,-828875,3407821,-9217717, 20837509,-41675018,74480265,-116145145,143502875, -78990635,-286097760,1453179125] |