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 | 1 |
| 1 | 12 |
| 2 | 126 |
| 3 | 1344 |
| 4 | 15120 |
| 5 | 181440 |
| 6 | 2328480 |
| 7 | 31933440 |
| 8 | 467026560 |
| 9 | 7264857600 |
| 10 | 119870150400 |
| 11 | 2092278988800 |
| 12 | 38532804710400 |
| 13 | 746943599001600 |
| 14 | 15205637551104000 |
| 15 | 324386934423552000 |
| 16 | 7237883474325504000 |
| 17 | 168600109166641152000 |
| 18 | 4093235983656787968000 |