The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 2 | 2 |
| 3 | 21 |
| 4 | 841 |
| 5 | 6652801 |
| 6 | 1037836801 |
| 7 | 59281238016001 |
| 8 | 20274183401472001 |
| 9 | 4308669456480829440001 |
| 10 | 1473626998956616992423936000001 |
| 11 | 1370473109029653802954260480000001 |
[2,21,841,6652801,1037836801,59281238016001, 20274183401472001,4308669456480829440001, 1473626998956616992423936000001, 1370473109029653802954260480000001] |