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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 0 |
| 4 | 5 |
| 5 | -3 |
| 6 | 18 |
| 7 | -17 |
| 8 | 65 |
| 9 | -80 |
| 10 | 241 |
| 11 | -351 |
| 12 | 914 |
| 13 | -1485 |
| 14 | 3525 |
| 15 | -6152 |
| 16 | 13757 |
| 17 | -25163 |
| 18 | 54130 |
| 19 | -102105 |
| 20 | 214169 |
| 21 | -412224 |
| 22 | 850521 |
| 23 | -1658855 |
| 24 | 3385970 |
| 25 | -6661493 |
| 26 | 13501693 |
| 27 | -26714232 |
| 28 | 53896325 |
| 29 | -107035635 |
| 30 | 215296146 |
| 31 | -428610401 |
| 32 | 860427569 |
| 33 | -1715666480 |
| 34 | 3439728385 |
| 35 | -6865872687 |
[1,1,0,5,-3,18,-17,65,-80,241,-351,914,-1485,3525, -6152,13757,-25163,54130,-102105,214169,-412224, 850521,-1658855,3385970,-6661493,13501693, -26714232,53896325,-107035635,215296146, -428610401,860427569,-1715666480,3439728385, -6865872687] |