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 | 11 |
| 3 | 76 |
| 4 | 430 |
| 5 | 2886 |
| 6 | 19215 |
| 7 | 127535 |
| 8 | 847604 |
| 9 | 5631313 |
| 10 | 37416247 |
| 11 | 248600404 |
| 12 | 1651756796 |
| 13 | 10974620983 |
| 14 | 72917744789 |
| 15 | 484481101148 |
| 16 | 3218996316583 |
| 17 | 21387701319096 |
| 18 | 142104471542165 |
| 19 | 944172564092345 |
| 20 | 6273284870138765 |