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 | 1 |
| 2 | 3 |
| 3 | 14 |
| 4 | 78 |
| 5 | 477 |
| 6 | 3094 |
| 7 | 20905 |
| 8 | 145547 |
| 9 | 1036891 |
| 10 | 7522335 |
| 11 | 55382045 |
| 12 | 412740298 |
| 13 | 3107671807 |
| 14 | 23604165913 |
| 15 | 180641336755 |
| 16 | 1391555475647 |
| 17 | 10781886600707 |
| 18 | 83968131035849 |
| 19 | 656931982467460 |
| 20 | 5160714860765430 |
| 21 | 40692065290732340 |
| 22 | 321937030883130021 |