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 | 0 |
| 1 | 1 |
| 2 | 1 |
| 3 | 11 |
| 4 | 47 |
| 5 | 727 |
| 6 | 7141 |
| 7 | 151427 |
| 8 | 2366603 |
| 9 | 64131559 |
| 10 | 1636722341 |
| 11 | 57208085801 |
| 12 | 1916138684507 |
| 13 | 85982424199597 |
| 14 | 3392993977055461 |
| 15 | 172553478253276697 |
| 16 | 8530444564835173531 |
| 17 | 535885387802465283059 |
| 18 | 30766248305796169627529 |