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 | 3 |
| 2 | 6 |
| 3 | 720 |
| 4 | 10080 |
| 5 | 40320 |
| 6 | 288 |
| 7 | 3251404800 |
| 8 | 33443020800 |
| 9 | 10032906240 |
| 10 | 150493593600 |
| 11 | 1179600089304268800000 |
| 12 | 6494947622660923209343932825600000000 |
| 13 | 817033558319976619871285124179533435912396304547840000000000000 |