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 | 721 |
| 5 | 5702401 |
| 6 | 889574401 |
| 7 | 50812489728001 |
| 8 | 17377871486976001 |
| 9 | 3693145248412139520001 |
| 10 | 1263108856248528850649088000001 |
| 11 | 1174691236311131831103651840000001 |