The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 5 | 1 |
| 6 | 4 |
| 7 | 10 |
| 8 | 22 |
| 9 | 55 |
| 10 | 188 |
| 11 | 612 |
| 12 | 2433 |
| 13 | 12227 |
| 14 | 68641 |
| 15 | 419235 |
| 16 | 2949869 |
| 17 | 24062426 |
| 18 | 221080988 |
| 19 | 2326692356 |
[1,4,10,22,55,188,612,2433,12227,68641,419235, 2949869,24062426,221080988,2326692356] |