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) |
|---|---|
| 2 | 1 |
| 3 | 1 |
| 4 | 3 |
| 5 | 11 |
| 6 | 35 |
| 7 | 107 |
| 8 | 319 |
| 9 | 935 |
| 10 | 2713 |
| 11 | 7825 |
| 12 | 22491 |
| 13 | 64523 |
| 14 | 184945 |
| 15 | 530001 |
| 16 | 1519151 |
| 17 | 4356471 |
| 18 | 12501301 |
| 19 | 35901325 |
| 20 | 103188123 |
| 21 | 296844379 |
| 22 | 854701935 |
| 23 | 2463133311 |
| 24 | 7104685935 |
| 25 | 20510632575 |
| 26 | 59262772629 |
| 27 | 171373598341 |
| 28 | 495968905267 |