The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 26 |
| 4 | 425 |
| 5 | 10647 |
| 6 | 365512 |
| 7 | 16067454 |
| 8 | 864721566 |
| 9 | 55202528425 |
| 10 | 4083666929771 |
| 11 | 343854336973368 |
| 12 | 32493430569907125 |
| 13 | 3406873823160467912 |
| 14 | 392619681705581846700 |
| 15 | 49342834390595374213214 |
| 16 | 6717520607597479710109299 |
| 17 | 984991858956314599670220717 |
| 18 | 154785386247352261724279606367 |
[1,1,3,26,425,10647,365512,16067454,864721566, 55202528425,4083666929771,343854336973368, 32493430569907125,3406873823160467912, 392619681705581846700,49342834390595374213214, 6717520607597479710109299, 984991858956314599670220717, 154785386247352261724279606367] |