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 | 1 |
| 2 | 36 |
| 3 | 291600 |
| 4 | 1851776640000 |
| 5 | 23813032808678400000000 |
| 6 | 1333916640950593574375424000000000000 |
| 7 | 618764594221522786972353235328676003840000000000000000 |