The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 13 |
| 4 | 57 |
| 5 | 189 |
| 6 | 849 |
| 7 | 3085 |
| 8 | 14289 |
| 9 | 54329 |
| 10 | 256973 |
| 11 | 1007905 |
| 12 | 4823589 |
| 13 | 19409469 |
| 14 | 93423353 |
| 15 | 384022225 |
| 16 | 1854215189 |
| 17 | 7752448757 |
| 18 | 37533638481 |
| 19 | 158987479205 |
| 20 | 771992164281 |
| 21 | 3303178546277 |
| 22 | 16085325165569 |
| 23 | 69393971221993 |
| 24 | 338748130781669 |
| 25 | 1471878925891841 |
| 26 | 7198407214886797 |
| 27 | 31477873307999261 |
[1,1,5,13,57,189,849,3085,14289,54329,256973, 1007905,4823589,19409469,93423353,384022225, 1854215189,7752448757,37533638481,158987479205, 771992164281,3303178546277,16085325165569, 69393971221993,338748130781669,1471878925891841, 7198407214886797,31477873307999261] |