The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 29 |
| 5 | 249 |
| 6 | 4021 |
| 7 | 99935 |
| 8 | 4398251 |
| 9 | 362789159 |
| 10 | 47338031953 |
| 11 | 10727733486159 |
| 12 | 4071858369077715 |
[1,1,1,29,249,4021,99935,4398251,362789159, 47338031953,10727733486159,4071858369077715] |