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 | 1 |
| 4 | 5 |
| 5 | 21 |
| 6 | 61 |
| 7 | 281 |
| 8 | 1961 |
| 9 | 10585 |
| 10 | 59641 |
| 11 | 509521 |
| 12 | 4086061 |
| 13 | 29792621 |
| 14 | 288051765 |
| 15 | 2997900361 |
| 16 | 27857436881 |
| 17 | 302238265841 |
| 18 | 3759751338481 |
| 19 | 43054257392545 |
| 20 | 526471319508181 |
| 21 | 7463835257515141 |
| 22 | 101755979383832621 |
| 23 | 1404876681654178041 |
| 24 | 22115830210157954425 |