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 | 2 |
| 3 | 6 |
| 4 | 12 |
| 5 | 120 |
| 6 | 60 |
| 7 | 7560 |
| 8 | 360 |
| 9 | 1260 |
| 10 | 2520 |
| 11 | 294053760 |
| 12 | 5040 |
| 13 | 128501493120 |
| 14 | 332640 |
| 15 | 110880 |
| 16 | 55440 |
| 17 | 106858629141264000 |
| 18 | 277200 |
| 19 | 188391763176048432000 |
| 20 | 720720 |
| 21 | 21621600 |
| 22 | 27935107200 |
| 23 | 1356699703068812438127792000 |
| 24 | 3603600 |
| 25 | 857656800 |
| 26 | 18632716502400 |
| 27 | 227026800 |
| 28 | 183783600 |