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) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 11 |
| 3 | 315 |
| 4 | 17129 |
| 5 | 1510425 |
| 6 | 196385475 |
| 7 | 35327367075 |
| 8 | 8399994587985 |
| 9 | 2550903574364145 |
| 10 | 963207568455370875 |
| 11 | 442613044315692124875 |
| 12 | 243195136160954426677305 |
| 13 | 157442856285298191126143625 |
| 14 | 118607799383105394973766029875 |
| 15 | 102867257381973743111023517821875 |