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 | 4 |
| 2 | 48 |
| 3 | 1080 |
| 4 | 60480 |
| 5 | 5544000 |
| 6 | 622702080 |
| 7 | 106661318400 |
| 8 | 28405593216000 |
| 9 | 8247280940236800 |
| 10 | 3294906785089920000 |
| 11 | 1595754032207182848000 |
| 12 | 840201424492187197440000 |
| 13 | 653671274699431372640256000 |