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 | 2 |
| 2 | 7 |
| 3 | 17 |
| 4 | 209 |
| 5 | 773 |
| 6 | 13327 |
| 7 | 65461 |
| 8 | 1441729 |
| 9 | 1255151 |
| 10 | 234662231 |
| 11 | 1702678841 |
| 12 | 53334454417 |
| 13 | 448162154317 |
| 14 | 16083557845279 |
| 15 | 13946689584823 |
| 16 | 126523856174033 |
| 17 | 66120494322107921 |
| 18 | 269906478537389909 |
| 19 | 34987413853951524577 |