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 | 3 |
| 4 | 11 |
| 5 | 52 |
| 6 | 307 |
| 7 | 1936 |
| 8 | 13207 |
| 9 | 93496 |
| 10 | 683988 |
| 11 | 5127163 |
| 12 | 39230669 |
| 13 | 305299420 |
| 14 | 2410624122 |
| 15 | 19273255184 |
| 16 | 155780437711 |
| 17 | 1271253542364 |
| 18 | 10462650241996 |
| 19 | 86765190816362 |
| 20 | 724450039738076 |
| 21 | 6086167189623746 |
| 22 | 51416796881915019 |