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) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 8 |
| 3 | 15 |
| 4 | 384 |
| 5 | 945 |
| 6 | 46080 |
| 7 | 135135 |
| 8 | 10321920 |
| 9 | 34459425 |
| 10 | 3715891200 |
| 11 | 13749310575 |
| 12 | 1961990553600 |
| 13 | 7905853580625 |
| 14 | 1428329123020800 |
| 15 | 6190283353629375 |
| 16 | 1371195958099968000 |
| 17 | 6332659870762850625 |
| 18 | 1678343852714360832000 |