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) |
|---|---|
| 3 | 3 |
| 4 | 9 |
| 5 | 41 |
| 6 | 241 |
| 7 | 1681 |
| 8 | 13441 |
| 9 | 120961 |
| 10 | 1209601 |
| 11 | 13305601 |
| 12 | 159667201 |
| 13 | 2075673601 |
| 14 | 29059430401 |
| 15 | 435891456001 |
| 16 | 6974263296001 |
| 17 | 118562476032001 |
| 18 | 2134124568576001 |
| 19 | 40548366802944001 |
| 20 | 810967336058880001 |