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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | -3 |
| 2 | 6 |
| 3 | -9 |
| 4 | 21 |
| 5 | -33 |
| 6 | 72 |
| 7 | -120 |
| 8 | 249 |
| 9 | -432 |
| 10 | 867 |
| 11 | -1545 |
| 12 | 3033 |
| 13 | -5502 |
| 14 | 10644 |
| 15 | -19539 |
| 16 | 37434 |
| 17 | -69261 |
| 18 | 131841 |
| 19 | -245217 |
| 20 | 464784 |
| 21 | -867492 |
| 22 | 1639569 |
| 23 | -3067260 |
| 24 | 5786199 |
| 25 | -10841349 |
| 26 | 20425857 |
| 27 | -38310246 |
| 28 | 72118920 |
| 29 | -135356595 |
| 30 | 254667006 |
| 31 | -478188705 |
| 32 | 899357613 |
[0,-3,6,-9,21,-33,72,-120,249,-432,867,-1545,3033, -5502,10644,-19539,37434,-69261,131841,-245217, 464784,-867492,1639569,-3067260,5786199,-10841349, 20425857,-38310246,72118920,-135356595,254667006, -478188705,899357613] |