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 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 2 |
| 6 | 3 |
| 7 | 5 |
| 8 | 11 |
| 9 | 27 |
| 10 | 86 |
| 11 | 351 |
| 12 | 1895 |
| 13 | 12673 |
| 14 | 100841 |
| 15 | 906332 |
| 16 | 8943750 |
| 17 | 95165384 |
| 18 | 1081035906 |
| 19 | 13027523553 |
| 20 | 165835586734 |
| 21 | 2222527601208 |
| 22 | 31273800434817 |
| 23 | 460941981112256 |
| 24 | 7101107185967292 |
| 25 | 114127691657536897 |
| 26 | 1910229280483131905 |
| 27 | 33244227211086415436 |