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 | 12 |
| 4 | 73 |
| 5 | 580 |
| 6 | 5601 |
| 7 | 63994 |
| 8 | 844929 |
| 9 | 12647016 |
| 10 | 211616785 |