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 | 1 |
| 2 | 4 |
| 3 | 3 |
| 4 | 32 |
| 5 | 75 |
| 6 | 216 |
| 7 | 3577 |
| 8 | 5888 |
| 9 | 15741 |
| 10 | 106300 |
| 11 | 13486539 |
| 12 | 9903168 |
| 13 | 56280729661 |
| 14 | 710986864 |
| 15 | 265553865 |
| 16 | 127626606592 |
| 17 | 450185515446285 |
| 18 | 1848730221900 |
| 19 | 603652082270808125 |
| 20 | 187926090380000 |
| 21 | 9545933933230947 |