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 | 6 |
| 3 | 24 |
| 4 | 228 |
| 5 | 3936 |
| 6 | 132624 |
| 7 | 8762040 |
| 8 | 1156532424 |
| 9 | 306700450536 |
| 10 | 164818597404924 |
| 11 | 180360080611682424 |
| 12 | 403600060221250880496 |
| 13 | 1853096813379189131728692 |
| 14 | 17504763708306471241857275208 |