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) |
|---|---|
| 4 | 1 |
| 5 | 121 |
| 6 | 11011 |
| 7 | 925771 |
| 8 | 75913222 |
| 9 | 6174066262 |
| 10 | 500777836042 |
| 11 | 40581331447162 |
| 12 | 3287582741506063 |
| 13 | 266307564861468823 |
| 14 | 21571273555248777493 |
| 15 | 1747282899667791058573 |
| 16 | 141530177899268957392924 |
| 17 | 11463951511551877750726204 |
| 18 | 928580264181940191843785764 |
| 19 | 75215006575885931519565302404 |