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) |
|---|---|
| 1 | 13 |
| 2 | 169 |
| 3 | 426 |
| 4 | 2190 |
| 5 | 9668 |
| 6 | 41112 |
| 7 | 186002 |
| 8 | 828530 |
| 9 | 3625724 |
| 10 | 16156680 |
| 11 | 71713022 |
| 12 | 316670472 |
| 13 | 1405263307 |
| 14 | 6230358367 |
| 15 | 27580548686 |
| 16 | 122260297698 |
| 17 | 541844851805 |
| 18 | 2400338788073 |
| 19 | 10637278675771 |
| 20 | 47137626165435 |
| 21 | 208858393685960 |