The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 6 | 1 |
| 7 | 37 |
| 8 | 894 |
| 9 | 18199 |
| 10 | 342140 |
| 11 | 6205428 |
| 12 | 111199318 |
| 13 | 1996955286 |
| 14 | 36267229831 |
| 15 | 670222865921 |
[1,37,894,18199,342140,6205428,111199318, 1996955286,36267229831,670222865921] |