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) |
|---|---|
| 1 | 1 |
| 2 | 6 |
| 3 | 180 |
| 4 | 37800 |
| 5 | 87318000 |
| 6 | 2622159540000 |
| 7 | 1338638666765400000 |
| 8 | 12984380089637682726000000 |
| 9 | 2896722619368127899492763620000000 |
| 10 | 18740906719713843949122453226304292600000000 |