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) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 4 |
| 3 | 36 |
| 4 | 324 |
| 5 | 15164 |
| 6 | 2287607 |
| 7 | 162104000 |
| 8 | 37905894000 |
| 9 | 4059346088384 |
| 10 | 718058901423168 |
| 11 | 221630954408019520 |