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 | 0 |
| 1 | 0 |
| 2 | 0 |
| 3 | 24 |
| 4 | 3490848 |
| 5 | 3501104400 |
| 6 | 564523119840 |
| 7 | 31643453033640 |
| 8 | 886834653776064 |
| 9 | 15220684846368288 |
| 10 | 181298924180884800 |
| 11 | 1627952400490177080 |
| 12 | 11672280987833510880 |
| 13 | 69664869701930893104 |
| 14 | 357038627052783076128 |
| 15 | 1609181428647593728200 |
| 16 | 6498071673405936462720 |