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 | 2 |
| 3 | 4 |
| 4 | 12 |
| 5 | 36 |
| 6 | 144 |
| 7 | 576 |
| 8 | 2304 |
| 9 | 11520 |
| 10 | 57600 |
| 11 | 345600 |
| 12 | 2073600 |
| 13 | 12441600 |
| 14 | 74649600 |
| 15 | 522547200 |
| 16 | 3657830400 |
| 17 | 29262643200 |
| 18 | 234101145600 |
| 19 | 1872809164800 |
| 20 | 14982473318400 |
| 21 | 134842259865600 |
| 22 | 1213580338790400 |
| 23 | 10922223049113600 |
| 24 | 109222230491136000 |
| 25 | 1092222304911360000 |