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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | -2 |
| 2 | 5 |
| 3 | -12 |
| 4 | 27 |
| 5 | -58 |
| 6 | 120 |
| 7 | -239 |
| 8 | 456 |
| 9 | -826 |
| 10 | 1397 |
| 11 | -2130 |
| 12 | 2666 |
| 13 | -1727 |
| 14 | -4308 |
| 15 | 24597 |
| 16 | -80658 |
| 17 | 220301 |
| 18 | -544803 |
| 19 | 1259278 |
| 20 | -2760324 |
| 21 | 5775490 |
| 22 | -11553490 |
| 23 | 22039330 |
| 24 | -39774088 |
| 25 | 66751007 |
| 26 | -100238388 |
| 27 | 120817159 |
| 28 | -61934817 |
| 29 | -261953355 |
| 30 | 1315627072 |
| 31 | -4183664882 |
| 32 | 11262428169 |
| 33 | -27602763180 |
[1,-2,5,-12,27,-58,120,-239,456,-826,1397,-2130, 2666,-1727,-4308,24597,-80658,220301,-544803, 1259278,-2760324,5775490,-11553490,22039330, -39774088,66751007,-100238388,120817159,-61934817, -261953355,1315627072,-4183664882,11262428169, -27602763180] |