The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 8 |
| 3 | 17 |
| 4 | 44 |
| 5 | 125 |
| 6 | 368 |
| 7 | 1097 |
| 8 | 3284 |
| 9 | 9845 |
| 10 | 29528 |
| 11 | 88577 |
| 12 | 265724 |
| 13 | 797165 |
| 14 | 2391488 |
| 15 | 7174457 |
| 16 | 21523364 |
| 17 | 64570085 |
| 18 | 193710248 |
| 19 | 581130737 |
| 20 | 1743392204 |
| 21 | 5230176605 |
| 22 | 15690529808 |
| 23 | 47071589417 |
| 24 | 141214768244 |
| 25 | 423644304725 |
| 26 | 1270932914168 |
| 27 | 3812798742497 |
| 28 | 11438396227484 |
[1,3,8,17,44,125,368,1097,3284,9845,29528,88577, 265724,797165,2391488,7174457,21523364,64570085, 193710248,581130737,1743392204,5230176605, 15690529808,47071589417,141214768244,423644304725, 1270932914168,3812798742497,11438396227484] |