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 | 3 |
| 4 | 9 |
| 5 | 38 |
| 6 | 198 |
| 7 | 1229 |
| 8 | 8819 |
| 9 | 71825 |
| 10 | 654985 |
| 11 | 6615932 |
| 12 | 73357572 |
| 13 | 886078937 |
| 14 | 11583028581 |
| 15 | 162939646239 |
| 16 | 2454350815033 |
| 17 | 39415438078466 |
| 18 | 672282146765650 |
| 19 | 12137067564016917 |
| 20 | 231223273420524311 |
| 21 | 4635720862911035149 |
| 22 | 97565878042828417209 |
| 23 | 2150797149322137710488 |