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 | 43 |
| 3 | 519 |
| 4 | 12259 |
| 5 | 570911 |
| 6 | 52683885 |
| 7 | 9661943973 |
| 8 | 3529267255201 |
| 9 | 2571928557261907 |
| 10 | 3744070741500225585 |
| 11 | 10898903552323266521821 |
| 12 | 63494356952926436300329797 |
| 13 | 740796894931520786982829942993 |