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 | 1 |
| 2 | 6 |
| 3 | 40 |
| 4 | 1728 |
| 5 | 10560 |
| 6 | 604800 |
| 7 | 4386816 |
| 8 | 348364800 |
| 9 | 76859228160 |
| 10 | 490311843840 |
| 11 | 172454510592000 |
| 12 | 6951148594790400 |
| 13 | 54188395462656000 |
| 14 | 5673488083845120000 |
| 15 | 2112698895984230400000 |
| 16 | 458667310457770160947200 |