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) |
|---|---|
| 1 | 0 |
| 2 | 9 |
| 3 | 30 |
| 4 | 316 |
| 5 | 2998 |
| 6 | 28089 |
| 7 | 268615 |
| 8 | 2552014 |
| 9 | 24338903 |
| 10 | 231985285 |
| 11 | 2211326264 |
| 12 | 21081277233 |
| 13 | 200957956858 |
| 14 | 1915723519711 |
| 15 | 18262175095417 |
| 16 | 174090604742721 |
| 17 | 1659575837493437 |
| 18 | 15820464143773812 |
| 19 | 150813856777262673 |