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 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 0 |
| 7 | 720 |
| 8 | 5760 |
| 9 | 25920 |
| 10 | 86400 |
| 11 | 237600 |
| 12 | 570240 |
| 13 | 1235520 |
| 14 | 892045440 |
| 15 | 13348249200 |
| 16 | 106757164800 |
| 17 | 604924594560 |
| 18 | 2722120577280 |
| 19 | 10344007402560 |
| 20 | 34479959558400 |
| 21 | 24928970490633600 |
| 22 | 546446134633639680 |
| 23 | 6281586217487489040 |
| 24 | 50248618811434961280 |