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 | 2 |
| 3 | 12 |
| 4 | 1680 |
| 5 | 2162160 |
| 6 | 4626053752320000 |
| 7 | 13644281345408020027550269440000 |
| 8 | 4402827357584746886229433170489943024971625310770489684257669120000000000 |