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 | 4 |
| 2 | 32 |
| 3 | 432 |
| 4 | 3840 |
| 5 | 64400 |
| 6 | 373248 |
| 7 | 7613424 |
| 8 | 56217600 |
| 9 | 765889344 |
| 10 | 6913984000 |
| 11 | 114117380608 |
| 12 | 599824465920 |
| 13 | 13796450740800 |
| 14 | 98909341090560 |
| 15 | 1356399209088000 |
| 16 | 11341872916070400 |
| 17 | 202178811399717504 |
| 18 | 1171410130065973248 |
| 19 | 24463636179365818512 |
| 20 | 176391086415667200000 |