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 | 2 |
| 4 | 5 |
| 5 | 11 |
| 6 | 31 |
| 7 | 106 |
| 8 | 337 |
| 9 | 1206 |
| 10 | 5031 |
| 11 | 20241 |
| 12 | 86901 |
| 13 | 421422 |
| 14 | 2014377 |
| 15 | 10015461 |
| 16 | 54946881 |
| 17 | 301009311 |
| 18 | 1692429867 |
| 19 | 10319449158 |
| 20 | 63321896601 |
| 21 | 395830490301 |
| 22 | 2648669976261 |
| 23 | 17920165424382 |
| 24 | 122976000215289 |
| 25 | 894420751179276 |
| 26 | 6596034524038701 |
| 27 | 49207275464475051 |