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 | 1 |
| 3 | 16 |
| 4 | 744 |
| 5 | 56256 |
| 6 | 6385920 |
| 7 | 1018114560 |
| 8 | 217234805760 |
| 9 | 59809766768640 |
| 10 | 20651520261980160 |
| 11 | 8740913386202726400 |
| 12 | 4451168534087349043200 |
| 13 | 2685007039858238501683200 |
| 14 | 1893459488121880710532300800 |
| 15 | 1543515756205349079583241011200 |
| 16 | 1440363330182802737753009160192000 |