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 | 2 |
| 2 | 3 |
| 3 | 3 |
| 4 | 5 |
| 5 | 12 |
| 6 | 50 |
| 7 | 289 |
| 8 | 2032 |
| 9 | 16384 |
| 10 | 147817 |
| 11 | 1471633 |
| 12 | 16002504 |
| 13 | 188441358 |
| 14 | 2385787007 |
| 15 | 32281229769 |
| 16 | 464479506181 |
| 17 | 7076959159858 |
| 18 | 113762276632726 |
| 19 | 1923164965554837 |
| 20 | 34092037061635649 |
| 21 | 632112131123669460 |