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 | 2 |
| 2 | 257 |
| 3 | 8519971 |
| 4 | 36574494881 |
| 5 | 140739702949921 |
| 6 | 140773995710729 |
| 7 | 140774004099109 |