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 | 3 |
| 3 | 60 |
| 4 | 12600 |
| 5 | 38102400 |
| 6 | 2112397056000 |
| 7 | 2609908810629120000 |
| 8 | 84645606509847871488000000 |
| 9 | 82967862872337478796810649600000000 |
| 10 | 2781259372192376861719959017613164544000000000 |