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 | 1 |
| 2 | 3 |
| 3 | 13 |
| 4 | 64 |
| 5 | 404 |
| 6 | 2135 |
| 7 | 21077 |
| 8 | 111459 |
| 9 | 1261637 |
| 10 | 10767866 |
| 11 | 111804384 |
| 12 | 659105457 |
| 13 | 18705101130 |