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) |
|---|---|
| 4 | 4 |
| 5 | 0 |
| 6 | 12 |
| 7 | 0 |
| 8 | 96 |
| 9 | 1296 |
| 10 | 1520 |
| 11 | 23540 |
| 12 | 101472 |
| 13 | 686724 |