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 | 3 |
| 2 | 5100 |
| 3 | 305727048000 |
| 4 | 7748770873210669158912000 |
| 5 | 476007332700693200670745550306381336371200000 |
| 6 | 272661655519533773844144991586798737775635133552905539740860416000000000 |