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 | 3 |
| 1 | 31 |
| 2 | 283 |
| 3 | 2551 |
| 4 | 22963 |
| 5 | 206671 |
| 6 | 1860043 |
| 7 | 16740391 |
| 8 | 150663523 |
| 9 | 1355971711 |
| 10 | 12203745403 |
| 11 | 109833708631 |
| 12 | 988503377683 |
| 13 | 8896530399151 |
| 14 | 80068773592363 |
| 15 | 720618962331271 |
| 16 | 6485570660981443 |
| 17 | 58370135948832991 |
| 18 | 525331223539496923 |