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 | 0 |
| 2 | 0 |
| 3 | 1 |
| 4 | 24 |
| 5 | 640 |
| 6 | 24000 |
| 7 | 1367296 |
| 8 | 122056704 |
| 9 | 17282252800 |
| 10 | 3897054412800 |
| 11 | 1400795928395776 |
| 12 | 802530102499344384 |
| 13 | 732523556206878392320 |
| 14 | 1064849635418836398243840 |
| 15 | 2464403435614136308036796416 |