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 | 4 |
| 2 | 44 |
| 3 | 372 |
| 4 | 2932 |
| 5 | 22484 |
| 6 | 170196 |
| 7 | 1279828 |
| 8 | 9590612 |
| 9 | 71736660 |
| 10 | 536055124 |
| 11 | 4003591508 |
| 12 | 29892900180 |
| 13 | 223162389844 |
| 14 | 1665861735764 |
| 15 | 12434781197652 |
| 16 | 92816950121812 |
| 17 | 692805066118484 |
| 18 | 5171207088198996 |
| 19 | 38598573880071508 |
| 20 | 288104312443589972 |
| 21 | 2150442403051689300 |