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 | 6 |
| 2 | 24 |
| 3 | 72 |
| 4 | 210 |
| 5 | 5400 |
| 6 | 30720 |
| 7 | 36960 |
| 8 | 51840 |
| 9 | 53760 |
| 10 | 120120 |
| 11 | 264600 |
| 12 | 887040 |
| 13 | 3991680 |
| 14 | 6912000 |
| 15 | 14968800 |
| 16 | 22118400 |
| 17 | 58198140 |
| 18 | 319334400 |
| 19 | 1703116800 |
| 20 | 4151347200 |
| 21 | 6273146880 |
| 22 | 12247200000 |
| 23 | 31757806080 |
| 24 | 42343741440 |
| 25 | 47636709120 |
| 26 | 70572902400 |
| 27 | 238378140000 |
| 28 | 442810368000 |