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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | -1 |
| 2 | 3 |
| 3 | -7 |
| 4 | 17 |
| 5 | -39 |
| 6 | 93 |
| 7 | -219 |
| 8 | 517 |
| 9 | -1219 |
| 10 | 2877 |
| 11 | -6787 |
| 12 | 16013 |
| 13 | -37779 |
| 14 | 89133 |
| 15 | -210291 |
| 16 | 496141 |
| 17 | -1170547 |
| 18 | 2761677 |
| 19 | -6515635 |
| 20 | 15372365 |
| 21 | -36268083 |
| 22 | 85567437 |
| 23 | -201879603 |
| 24 | 476295373 |
| 25 | -1123725619 |
| 26 | 2651210445 |
| 27 | -6255011635 |
| 28 | 14757474509 |
| 29 | -34817369907 |
| 30 | 82144763085 |
| 31 | -193804475187 |
[1,-1,3,-7,17,-39,93,-219,517,-1219,2877,-6787, 16013,-37779,89133,-210291,496141,-1170547, 2761677,-6515635,15372365,-36268083,85567437, -201879603,476295373,-1123725619,2651210445, -6255011635,14757474509,-34817369907,82144763085, -193804475187] |