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 | 6 |
| 3 | 16 |
| 4 | 45 |
| 5 | 72 |
| 6 | 404 |
| 7 | 456 |
| 8 | 2550 |
| 9 | 5144 |
| 10 | 26880 |
| 11 | 38568 |
| 12 | 367170 |
| 13 | 431776 |
| 14 | 3202964 |
| 15 | 8993712 |
| 16 | 33857520 |
| 17 | 63177816 |
| 18 | 636456776 |
| 19 | 803796696 |
| 20 | 6886253964 |
| 21 | 17456593904 |
| 22 | 79965511980 |
| 23 | 139069427016 |
| 24 | 1466861335900 |