The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 27 |
| 4 | 249 |
| 5 | 2825 |
| 6 | 41355 |
| 7 | 708883 |
| 8 | 13888497 |
| 9 | 309267729 |
| 10 | 7698772755 |
| 11 | 211585744139 |
| 12 | 6367841422569 |
| 13 | 208299923870233 |
| 14 | 7357493992966299 |
| 15 | 279095125351544835 |
| 16 | 11316313498670411745 |
| 17 | 488403056864943302177 |
| 18 | 22355228989851909617187 |
| 19 | 1081663315375339026249211 |
[1,1,3,27,249,2825,41355,708883,13888497, 309267729,7698772755,211585744139,6367841422569, 208299923870233,7357493992966299, 279095125351544835,11316313498670411745, 488403056864943302177,22355228989851909617187, 1081663315375339026249211] |