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 | 6 |
| 4 | 3 |
| 5 | 5 |
| 6 | 180 |
| 7 | 1260 |
| 8 | 105 |
| 9 | 945 |
| 10 | 9450 |
| 11 | 34650 |
| 12 | 155925 |
| 13 | 289575 |
| 14 | 12612600 |
| 15 | 1702701000 |
| 16 | 212837625 |
| 17 | 1206079875 |
| 18 | 21709437750 |
| 19 | 412479317250 |
| 20 | 2888510625 |
| 21 | 21655164155625 |
| 22 | 952827222847500 |
| 23 | 128158047517500 |
| 24 | 16436269594119375 |