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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | -1 |
| 2 | 3 |
| 3 | -6 |
| 4 | 14 |
| 5 | -30 |
| 6 | 67 |
| 7 | -147 |
| 8 | 325 |
| 9 | -716 |
| 10 | 1580 |
| 11 | -3484 |
| 12 | 7685 |
| 13 | -16949 |
| 14 | 37383 |
| 15 | -82450 |
| 16 | 181850 |
| 17 | -401082 |
| 18 | 884615 |
| 19 | -1951079 |
| 20 | 4303241 |
| 21 | -9491096 |
| 22 | 20933272 |
| 23 | -46169784 |
| 24 | 101830665 |
| 25 | -224594601 |
| 26 | 495358987 |
| 27 | -1092548638 |
| 28 | 2409691878 |
| 29 | -5314742742 |
| 30 | 11722034123 |
| 31 | -25853760123 |
| 32 | 57022262989 |
| 33 | -125766560100 |
[1,-1,3,-6,14,-30,67,-147,325,-716,1580,-3484, 7685,-16949,37383,-82450,181850,-401082,884615, -1951079,4303241,-9491096,20933272,-46169784, 101830665,-224594601,495358987,-1092548638, 2409691878,-5314742742,11722034123,-25853760123, 57022262989,-125766560100] |