The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 4 |
| 3 | 1835 |
| 4 | 53082012 |
| 5 | 30525244435834 |
| 6 | 310387893630465965693 |
| 7 | 55676868201599759013090066735 |
[1,4,1835,53082012,30525244435834, 310387893630465965693, 55676868201599759013090066735] |