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 | 4 |
| 1 | 12 |
| 2 | 60 |
| 3 | 360 |
| 4 | 3240 |
| 5 | 42120 |
| 6 | 842400 |
| 7 | 26114400 |
| 8 | 1279605600 |
| 9 | 99809236800 |
| 10 | 12476154600000 |
| 11 | 2507707074600000 |
| 12 | 812497092170400000 |
| 13 | 424935979205119200000 |
| 14 | 359070902428325724000000 |
| 15 | 490490852717092938984000000 |
| 16 | 1083494293652058302215656000000 |