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 | 3 |
| 2 | 23 |
| 3 | 201 |
| 4 | 1855 |
| 5 | 17643 |
| 6 | 171059 |
| 7 | 1680822 |
| 8 | 16679031 |
| 9 | 166763190 |
| 10 | 1677365833 |
| 11 | 16953705860 |
| 12 | 172047413395 |
| 13 | 1751870166998 |
| 14 | 17890003430490 |
| 15 | 183148065506136 |
| 16 | 1879053717936423 |
| 17 | 19315569214866495 |
| 18 | 198890064249729314 |
| 19 | 2051053032020625350 |
| 20 | 21180292180328586305 |