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 | 3 |
| 4 | 9 |
| 5 | 41 |
| 6 | 231 |
| 7 | 1551 |
| 8 | 12037 |
| 9 | 105861 |
| 10 | 1039539 |
| 11 | 11268059 |
| 12 | 133585089 |
| 13 | 1718984673 |
| 14 | 23857531519 |
| 15 | 355190381031 |
| 16 | 5646040979901 |
| 17 | 95432906354621 |
| 18 | 1709068974897867 |
| 19 | 32325104169244851 |
| 20 | 643869687410800249 |
| 21 | 13471540400560532889 |
| 22 | 295384662114697463319 |