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 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 2 |
| 5 | 8 |
| 6 | 8 |
| 7 | 48 |
| 8 | 72 |
| 9 | 576 |
| 10 | 1152 |
| 11 | 11520 |
| 12 | 28800 |
| 13 | 345600 |
| 14 | 1036800 |
| 15 | 14515200 |
| 16 | 50803200 |
| 17 | 812851200 |
| 18 | 3251404800 |
| 19 | 58525286400 |
| 20 | 263363788800 |
| 21 | 5267275776000 |
| 22 | 26336378880000 |
| 23 | 579400335360000 |
| 24 | 3186701844480000 |
| 25 | 76480844267520000 |
| 26 | 458885065605120000 |
| 27 | 11931011705733120000 |