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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | -7 |
| 2 | 35 |
| 3 | -169 |
| 4 | 803 |
| 5 | -3805 |
| 6 | 18011 |
| 7 | -85237 |
| 8 | 403355 |
| 9 | -1908709 |
| 10 | 9032123 |
| 11 | -42740485 |
| 12 | 202250171 |
| 13 | -957058117 |
| 14 | 4528847675 |
| 15 | -21430737349 |
| 16 | 101411338043 |
| 17 | -479883604165 |
| 18 | 2270833596731 |
| 19 | -10745699955397 |
| 20 | 50849198151995 |
| 21 | -240620989179589 |
| 22 | 1138630746165563 |
| 23 | -5388058541915845 |
[1,-7,35,-169,803,-3805,18011,-85237,403355, -1908709,9032123,-42740485,202250171,-957058117, 4528847675,-21430737349,101411338043, -479883604165,2270833596731,-10745699955397, 50849198151995,-240620989179589,1138630746165563, -5388058541915845] |