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 | 3 |
| 4 | 24 |
| 5 | 60 |
| 6 | 720 |
| 7 | 252 |
| 8 | 40320 |
| 9 | 36288 |
| 10 | 3628800 |
| 11 | 4989600 |
| 12 | 95800320 |
| 13 | 3113510400 |
| 14 | 17435658240 |
| 15 | 326918592000 |
| 16 | 20922789888000 |
| 17 | 2736057139200 |
| 18 | 6402373705728000 |
| 19 | 30411275102208 |
| 20 | 2432902008176640000 |
| 21 | 25545471085854720000 |
| 22 | 224800145555521536000 |