The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 4 |
| 3 | 5 |
| 4 | 9 |
| 5 | 279 |
| 6 | 15331 |
| 7 | 1685775 |
| 8 | 205670529 |
| 9 | 129734299239 |
| 10 | 148778622108171 |
[2,4,5,9,279,15331,1685775,205670529,129734299239, 148778622108171] |