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) |
|---|---|
| 8 | 1 |
| 9 | 9 |
| 10 | 90 |
| 11 | 825 |
| 12 | 7425 |
| 13 | 66924 |
| 14 | 609609 |
| 15 | 5643495 |
| 16 | 53275365 |
| 17 | 513949865 |
| 18 | 5072383602 |
| 19 | 51247279161 |
| 20 | 530162317815 |
| 21 | 5616049288500 |
| 22 | 60907673202255 |
| 23 | 676114396423257 |
| 24 | 7679484722988045 |
| 25 | 89216205660482175 |
| 26 | 1059689275333095550 |
| 27 | 12863300130089805825 |
| 28 | 159506272335882076605 |