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 | 7 |
| 2 | 47 |
| 3 | 307 |
| 4 | 1967 |
| 5 | 12427 |
| 6 | 77687 |
| 7 | 481747 |
| 8 | 2968607 |
| 9 | 18202267 |
| 10 | 111166727 |
| 11 | 676765987 |
| 12 | 4109424047 |
| 13 | 24900684907 |
| 14 | 150624812567 |
| 15 | 909852391027 |
| 16 | 5489631924287 |
| 17 | 33090379436347 |
| 18 | 199305216071207 |
| 19 | 1199645993692867 |