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 | 0 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 1 |
| 5 | 3 |
| 6 | 8 |
| 7 | 22 |
| 8 | 68 |
| 9 | 235 |
| 10 | 896 |
| 11 | 3700 |
| 12 | 16388 |
| 13 | 77424 |
| 14 | 388337 |
| 15 | 2058898 |
| 16 | 11494391 |
| 17 | 67345463 |
| 18 | 412884769 |
| 19 | 2641957682 |
| 20 | 17603708949 |
| 21 | 121891857559 |
| 22 | 875463364581 |
| 23 | 6511352351724 |
| 24 | 50074591410942 |
| 25 | 397627804820554 |
| 26 | 3256109939552809 |
| 27 | 27464891261741533 |
| 28 | 238366531369343096 |
| 29 | 2126510299723649140 |
| 30 | 19482346640311421722 |
| 31 | 183143139819128271540 |
| 32 | 1765079515780983078401 |