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 | 48 |
| 2 | 15120 |
| 3 | 7392000 |
| 4 | 4414410000 |
| 5 | 2956651746048 |
| 6 | 2133278987583744 |
| 7 | 1621682968820428800 |
| 8 | 1281351259836532170000 |
| 9 | 1043032815185819858400000 |
| 10 | 869343653096068540955685120 |
| 11 | 738637974389826550020188712960 |
| 12 | 637665137404661719206664998969600 |