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 | 84 |
| 4 | 1848 |
| 5 | 55440 |
| 6 | 2106720 |
| 7 | 96909120 |
| 8 | 5233092480 |
| 9 | 324451733760 |
| 10 | 22711621363200 |
| 11 | 1771506466329600 |
| 12 | 152349556104345600 |
| 13 | 14320858273808486400 |
| 14 | 1460727543928465612800 |
| 15 | 160680029832131217408000 |
| 16 | 18960243520191483654144000 |
| 17 | 2388990683544126940422144000 |