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 | 20 |
| 3 | 600 |
| 4 | 24000 |
| 5 | 1200000 |
| 6 | 72000000 |
| 7 | 5040000000 |
| 8 | 403200000000 |
| 9 | 36288000000000 |
| 10 | 3628800000000000 |
| 11 | 399168000000000000 |
| 12 | 47900160000000000000 |
| 13 | 6227020800000000000000 |
| 14 | 871782912000000000000000 |
| 15 | 130767436800000000000000000 |
| 16 | 20922789888000000000000000000 |