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) |
|---|---|
| 7 | 1 |
| 8 | 0 |
| 9 | 36 |
| 10 | 240 |
| 11 | 2970 |
| 12 | 34848 |
| 13 | 454740 |
| 14 | 6362928 |
| 15 | 95450355 |
| 16 | 1527194240 |
| 17 | 25962321528 |
| 18 | 467321755680 |
| 19 | 8879113408308 |
| 20 | 177582268088640 |
| 21 | 3729227629977720 |
| 22 | 82043007859339296 |
| 23 | 1886989180765048965 |
| 24 | 45287740338360829056 |