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 | 140737488355201 |
| 2 | 36028797018963841 |
| 3 | 10141204801825835211973625642881 |
| 4 | 11150372599265311570767859136324180752990081 |