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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | -2 |
| 2 | 4 |
| 3 | -9 |
| 4 | 22 |
| 5 | -57 |
| 6 | 153 |
| 7 | -419 |
| 8 | 1160 |
| 9 | -3230 |
| 10 | 9021 |
| 11 | -25234 |
| 12 | 70643 |
| 13 | -197849 |
| 14 | 554233 |
| 15 | -1552742 |
| 16 | 4350420 |
| 17 | -12189221 |
| 18 | 34152882 |
| 19 | -95693445 |
| 20 | 268125913 |
| 21 | -751270435 |
| 22 | 2105010556 |
| 23 | -5898105006 |
| 24 | 16526117921 |
| 25 | -46305146110 |
| 26 | 129744125671 |
| 27 | -363534946433 |
| 28 | 1018602262609 |
| 29 | -2854060085466 |
| 30 | 7996898607604 |
[1,-2,4,-9,22,-57,153,-419,1160,-3230,9021,-25234, 70643,-197849,554233,-1552742,4350420,-12189221, 34152882,-95693445,268125913,-751270435, 2105010556,-5898105006,16526117921,-46305146110, 129744125671,-363534946433,1018602262609, -2854060085466,7996898607604] |