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 | 2 |
| 2 | 48 |
| 3 | 288 |
| 4 | 138240 |
| 5 | 1382400 |
| 6 | 2090188800 |
| 7 | 29262643200 |
| 8 | 56184274944000 |
| 9 | 1011316948992000 |
| 10 | 1334938372669440000 |
| 11 | 29368644198727680000 |
| 12 | 11545401407403825561600000 |
| 13 | 300180436592499464601600000 |
| 14 | 50430313347539910053068800000 |
| 15 | 1512909400426197301592064000000 |