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 | 84 |
| 4 | 8548 |
| 5 | 4203520 |
| 6 | 8590557312 |
| 7 | 70368815480832 |
| 8 | 2305843028004192256 |
| 9 | 302231454912728264605696 |
| 10 | 158456325028538104598816096256 |
| 11 | 332306998946228986960926214931349504 |
| 12 | 2787593149816327892769293535238052808491008 |