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 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 2 |
| 6 | 12 |
| 7 | 12 |
| 8 | 48 |
| 9 | 144 |
| 10 | 1440 |
| 11 | 1440 |
| 12 | 17280 |
| 13 | 17280 |
| 14 | 241920 |
| 15 | 18144000 |
| 16 | 145152000 |
| 17 | 145152000 |
| 18 | 2612736000 |
| 19 | 2612736000 |
| 20 | 10450944000 |
| 21 | 219469824000 |
| 22 | 4828336128000 |
| 23 | 4828336128000 |
| 24 | 115880067072000 |
| 25 | 579400335360000 |
| 26 | 15064408719360000 |
| 27 | 135579678474240000 |
| 28 | 26573616980951040000 |
| 29 | 26573616980951040000 |