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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | -2 |
| 3 | 6 |
| 4 | -23 |
| 5 | 90 |
| 6 | -370 |
| 7 | 1568 |
| 8 | -6802 |
| 9 | 30032 |
| 10 | -134422 |
| 11 | 608136 |
| 12 | -2774480 |
| 13 | 12741844 |
| 14 | -58820272 |
| 15 | 272617696 |
| 16 | -1267318854 |
| 17 | 5904152560 |
| 18 | -27545442786 |
| 19 | 128610298720 |
| 20 | -600579852616 |
| 21 | 2803385644716 |
| 22 | -13072680693872 |
| 23 | 60864695165024 |
| 24 | -282763138097520 |
| 25 | 1309945271204312 |
| 26 | -6047009494466692 |
[1,-2,6,-23,90,-370,1568,-6802,30032,-134422, 608136,-2774480,12741844,-58820272,272617696, -1267318854,5904152560,-27545442786,128610298720, -600579852616,2803385644716,-13072680693872, 60864695165024,-282763138097520,1309945271204312, -6047009494466692] |