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 | 20 |
| 2 | 6400 |
| 3 | 32768000 |
| 4 | 2684354560000 |
| 5 | 3518437208883200000 |
| 6 | 73786976294838206464000000 |
| 7 | 24758800785707605497982484480000000 |
| 8 | 132922799578491587290380706028034457600000000 |