The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 5 | 1 |
| 6 | 4 |
| 7 | 13 |
| 8 | 28 |
| 9 | 111 |
| 10 | 502 |
| 11 | 1855 |
| 12 | 7742 |
| 13 | 47738 |
| 14 | 322725 |
| 15 | 2215451 |
| 16 | 20024605 |
| 17 | 210636607 |
[1,4,13,28,111,502,1855,7742,47738,322725,2215451, 20024605,210636607] |