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 | 2 |
| 1 | 24 |
| 2 | 72 |
| 3 | 2880 |
| 4 | 800 |
| 5 | 362880 |
| 6 | 169344 |
| 7 | 29030400 |
| 8 | 9331200 |
| 9 | 4790016000 |
| 10 | 8673280 |
| 11 | 31384184832000 |
| 12 | 6181733376000 |
| 13 | 439378587648000 |
| 14 | 10346434560000 |
| 15 | 512189896458240000 |
| 16 | 265423814656 |
| 17 | 14148260909088768000 |
| 18 | 2076423318208512000 |
| 19 | 96342919523794944000000 |
| 20 | 74538995631567667200000 |