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) |
|---|---|
| 4 | 4 |
| 5 | 60 |
| 6 | 720 |
| 7 | 8400 |
| 8 | 100800 |
| 9 | 1270080 |
| 10 | 16934400 |
| 11 | 239500800 |
| 12 | 3592512000 |
| 13 | 57081024000 |
| 14 | 958961203200 |
| 15 | 16999766784000 |
| 16 | 317328979968000 |
| 17 | 6224529991680000 |
| 18 | 128047474114560000 |
| 19 | 2757288942600192000 |
| 20 | 62039001208504320000 |
| 21 | 1456091851893719040000 |
| 22 | 35593356379624243200000 |