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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | -3 |
| 3 | 5 |
| 4 | -12 |
| 5 | 25 |
| 6 | -54 |
| 7 | 116 |
| 8 | -249 |
| 9 | 535 |
| 10 | -1149 |
| 11 | 2468 |
| 12 | -5301 |
| 13 | 11386 |
| 14 | -24456 |
| 15 | 52529 |
| 16 | -112827 |
| 17 | 242341 |
| 18 | -520524 |
| 19 | 1118033 |
| 20 | -2401422 |
| 21 | 5158012 |
| 22 | -11078889 |
| 23 | 23796335 |
| 24 | -51112125 |
| 25 | 109783684 |
| 26 | -235804269 |
| 27 | 506483762 |
| 28 | -1087875984 |
| 29 | 2336647777 |
[0,1,-3,5,-12,25,-54,116,-249,535,-1149,2468, -5301,11386,-24456,52529,-112827,242341,-520524, 1118033,-2401422,5158012,-11078889,23796335, -51112125,109783684,-235804269,506483762, -1087875984,2336647777] |