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 | 8 |
| 2 | 44 |
| 3 | 252 |
| 4 | 1446 |
| 5 | 8300 |
| 6 | 47642 |
| 7 | 273466 |
| 8 | 1569700 |
| 9 | 9010108 |
| 10 | 51718192 |
| 11 | 296863410 |
| 12 | 1704001644 |
| 13 | 9781001986 |
| 14 | 56143138234 |
| 15 | 322262685896 |
| 16 | 1849793972828 |
| 17 | 10617852738356 |
| 18 | 60946677537854 |
| 19 | 349835093256180 |
| 20 | 2008060117756986 |