| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3674160 |
| 3 | 43252003274489856000 |
| 4 | 7401196841564901869874093974498574336000000000 |
| 5 | 282870942277741856536180333107150328293127731985672134721536000000000000000 |
[1,3674160,43252003274489856000, 7401196841564901869874093974498574336000000000, 28287094227774185653618033310715032829312773198567\ 2134721536000000000000000] |