The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 2 | 1 |
| 3 | 3 |
| 4 | 14 |
| 5 | 55 |
| 6 | 231 |
| 7 | 952 |
| 8 | 3976 |
| 9 | 16614 |
| 10 | 69750 |
| 11 | 293557 |
| 12 | 1238952 |
| 13 | 5240599 |
[1,3,14,55,231,952,3976,16614,69750,293557, 1238952,5240599] |