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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 0 |
| 3 | 1 |
| 4 | -3 |
| 5 | 7 |
| 6 | -15 |
| 7 | 31 |
| 8 | -63 |
| 9 | 127 |
| 10 | -255 |
| 11 | 510 |
| 12 | -1011 |
| 13 | 1968 |
| 14 | -3717 |
| 15 | 6720 |
| 16 | -11439 |
| 17 | 17874 |
| 18 | -24309 |
| 19 | 24309 |
| 20 | 0 |
| 21 | -92358 |
| 22 | 352485 |
| 23 | -997569 |
| 24 | 2485242 |
| 25 | -5754024 |
| 26 | 12680955 |
| 27 | -26924184 |
| 28 | 55410642 |
| 29 | -110821283 |
| 30 | 215426355 |
| 31 | -406270425 |
| 32 | 740354804 |
| 33 | -1294617072 |
| 34 | 2145852303 |
[2,0,1,-3,7,-15,31,-63,127,-255,510,-1011,1968, -3717,6720,-11439,17874,-24309,24309,0,-92358, 352485,-997569,2485242,-5754024,12680955, -26924184,55410642,-110821283,215426355, -406270425,740354804,-1294617072,2145852303] |