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) |
|---|---|
| 11 | 2 |
| 12 | 2 |
| 13 | 6 |
| 14 | 12 |
| 15 | 12 |
| 16 | 24 |
| 17 | 60 |
| 18 | 180 |
| 19 | 360 |
| 20 | 1260 |
| 21 | 5040 |
| 22 | 15120 |
| 23 | 55440 |
| 24 | 166320 |
| 25 | 831600 |
| 26 | 4324320 |
| 27 | 36756720 |
| 28 | 367567200 |
| 29 | 2327925600 |
| 30 | 27935107200 |