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 | 1 |
| 1 | 1 |
| 2 | 8 |
| 3 | 6 |
| 4 | 144 |
| 5 | 480 |
| 6 | 5760 |
| 7 | 5040 |
| 8 | 524160 |
| 9 | 2177280 |
| 10 | 43545600 |
| 11 | 159667200 |
| 12 | 6706022400 |
| 13 | 49816166400 |
| 14 | 2092278988800 |
| 15 | 1307674368000 |
| 16 | 376610217984000 |
| 17 | 4623936565248000 |
| 18 | 128047474114560000 |
| 19 | 729870602452992000 |
| 20 | 77852864261652480000 |
| 21 | 613091306060513280000 |