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 | 6 |
| 4 | 24 |
| 5 | 24 |
| 6 | 144 |
| 7 | 144 |
| 8 | 1152 |
| 9 | 10368 |
| 10 | 20736 |
| 11 | 20736 |
| 12 | 248832 |
| 13 | 248832 |
| 14 | 497664 |
| 15 | 1492992 |
| 16 | 23887872 |
| 17 | 23887872 |
| 18 | 429981696 |
| 19 | 429981696 |
| 20 | 1719926784 |
| 21 | 5159780352 |
| 22 | 10319560704 |
| 23 | 10319560704 |
| 24 | 247669456896 |
| 25 | 247669456896 |
| 26 | 495338913792 |
| 27 | 13374150672384 |
| 28 | 53496602689536 |
| 29 | 53496602689536 |