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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 3 |
| 2 | -2 |
| 3 | 15 |
| 4 | -18 |
| 5 | 76 |
| 6 | -126 |
| 7 | 405 |
| 8 | -802 |
| 9 | 2241 |
| 10 | -4884 |
| 11 | 12696 |
| 12 | -29100 |
| 13 | 72903 |
| 14 | -171490 |
| 15 | 421683 |
| 16 | -1005030 |
| 17 | 2448356 |
| 18 | -5873706 |
| 19 | 14243001 |
| 20 | -34280258 |
| 21 | 82936965 |
| 22 | -199930344 |
| 23 | 483172656 |
| 24 | -1165648152 |
| 25 | 2815517835 |
| 26 | -6794932418 |
| 27 | 16408304343 |
| 28 | -39606671610 |
| 29 | 95629756540 |
[0,3,-2,15,-18,76,-126,405,-802,2241,-4884,12696, -29100,72903,-171490,421683,-1005030,2448356, -5873706,14243001,-34280258,82936965,-199930344, 483172656,-1165648152,2815517835,-6794932418, 16408304343,-39606671610,95629756540] |