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 | 1 |
| 3 | 6 |
| 4 | 29 |
| 5 | 140 |
| 6 | 704 |
| 7 | 3732 |
| 8 | 20915 |
| 9 | 123832 |
| 10 | 773051 |
| 11 | 5076174 |
| 12 | 34973432 |
| 13 | 252212600 |
| 14 | 1899483793 |
| 15 | 14908277490 |
| 16 | 121701247649 |
| 17 | 1031472019760 |
| 18 | 9061405440156 |
| 19 | 82384690078948 |
| 20 | 774102548613907 |
| 21 | 7507335441107420 |
| 22 | 75055820357153647 |
| 23 | 772694054961218802 |
| 24 | 8182814265240466788 |