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 | 1 |
| 3 | 3 |
| 4 | 6 |
| 5 | 18 |
| 6 | 58 |
| 7 | 251 |
| 8 | 1410 |
| 9 | 10311 |
| 10 | 98577 |
| 11 | 1246488 |
| 12 | 20837439 |
| 13 | 466087635 |