The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 1 |
| 3 | -3 |
| 4 | -3 |
| 5 | 3 |
| 6 | 9 |
| 7 | 9 |
| 8 | 9 |
| 9 | 27 |
| 10 | 81 |
| 11 | 189 |
| 12 | 405 |
| 13 | 891 |
| 14 | 2025 |
| 15 | 4617 |
| 16 | 10449 |
| 17 | 23571 |
| 18 | 53217 |
| 19 | 120285 |
| 20 | 271917 |
| 21 | 614547 |
| 22 | 1388745 |
| 23 | 3138345 |
| 24 | 7092441 |
| 25 | 16028523 |
| 26 | 36223281 |
| 27 | 81861597 |
| 28 | 185000517 |
| 29 | 418086603 |
| 30 | 944843049 |
| 31 | 2135270889 |
| 32 | 4825543329 |
| 33 | 10905346467 |
| 34 | 24645222081 |
| 35 | 55696256829 |
| 36 | 125869143645 |
[1,3,1,-3,-3,3,9,9,9,27,81,189,405,891,2025,4617, 10449,23571,53217,120285,271917,614547,1388745, 3138345,7092441,16028523,36223281,81861597, 185000517,418086603,944843049,2135270889, 4825543329,10905346467,24645222081,55696256829, 125869143645] |