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 | 3 |
| 3 | 32 |
| 4 | 135 |
| 5 | 3456 |
| 6 | 3500 |
| 7 | 172800 |
| 8 | 694575 |
| 9 | 6272000 |
| 10 | 6286896 |
| 11 | 762048000 |
| 12 | 763062300 |
| 13 | 129090931200 |
| 14 | 129196782000 |
| 15 | 129282177024 |
| 16 | 517408266375 |
| 17 | 149597947699200 |
| 18 | 149654059755200 |
| 19 | 54042258606336000 |
| 20 | 54056895051375216 |