This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
| n | a(n) |
|---|---|
| 1 | 7 |
| 2 | 31 |
| 3 | 181 |
| 4 | 1556755201 |
| 5 | 12772735542927360001 |
| 6 | 3877802510832746496000001 |
| 7 | 65782709233423382541804503040000001 |
| 8 | 203978820811974433586402817399028973568000000001 |