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) |
|---|---|
| 2 | 1 |
| 3 | 3 |
| 4 | 12 |
| 5 | 80 |
| 6 | 960 |
| 7 | 21504 |
| 8 | 917504 |
| 9 | 75497472 |
| 10 | 12079595520 |
| 11 | 3779571220480 |
| 12 | 2322168557862912 |
| 13 | 2810246167479189504 |
| 14 | 6714614842830276788224 |
| 15 | 31734302764884015836037120 |
| 16 | 297105609428491265975789813760 |
| 17 | 5516815412193254355313652349796352 |