The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 10 |
| 5 | 39 |
| 6 | 160 |
| 7 | 691 |
| 8 | 3081 |
| 9 | 14095 |
| 10 | 65757 |
| 11 | 311695 |
| 12 | 1496833 |
| 13 | 7267009 |
[1,1,3,10,39,160,691,3081,14095,65757,311695, 1496833,7267009] |