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 | 8 |
| 3 | 48 |
| 4 | 392 |
| 5 | 1992 |
| 6 | 7488 |
| 7 | 53712 |
| 8 | 249992 |
| 9 | 1831056 |
| 10 | 6249992 |
| 11 | 45781056 |
| 12 | 48217776 |
| 13 | 170312312 |
| 14 | 1144531056 |
| 15 | 1205467776 |
| 16 | 1217651376 |
| 17 | 4514058432 |
| 18 | 4576557032 |
| 19 | 22460937432 |
| 20 | 28613281056 |
| 21 | 28671874056 |
| 22 | 30136717776 |
| 23 | 30441401376 |