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 | 2 |
| 3 | 6 |
| 4 | 18 |
| 5 | 57 |
| 6 | 191 |
| 7 | 660 |
| 8 | 2334 |
| 9 | 8417 |
| 10 | 30831 |
| 11 | 114380 |
| 12 | 428915 |
| 13 | 1623143 |
| 14 | 6190876 |
| 15 | 23774613 |
| 16 | 91849846 |
| 17 | 356735941 |
| 18 | 1392091107 |
| 19 | 5455425618 |
| 20 | 21460947111 |
| 21 | 84717452192 |
| 22 | 335479515201 |
| 23 | 1332327233554 |
| 24 | 5305235886691 |
| 25 | 21176621863427 |
| 26 | 84720103674498 |