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 | 0 |
| 2 | 4 |
| 3 | 36 |
| 4 | 307 |
| 5 | 2848 |
| 6 | 25651 |
| 7 | 231031 |
| 8 | 2106565 |
| 9 | 19307362 |
| 10 | 177948719 |
| 11 | 1649246163 |
| 12 | 15360077721 |
| 13 | 143683073300 |