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 | 4 |
| 4 | 12 |
| 5 | 24 |
| 6 | 48 |
| 7 | 144 |
| 8 | 720 |
| 9 | 1440 |
| 10 | 10080 |
| 11 | 30240 |
| 12 | 60480 |
| 13 | 302400 |
| 14 | 604800 |
| 15 | 6652800 |
| 16 | 19958400 |
| 17 | 259459200 |
| 18 | 518918400 |
| 19 | 3632428800 |
| 20 | 61751289600 |
| 21 | 185253868800 |
| 22 | 926269344000 |
| 23 | 17599117536000 |
| 24 | 35198235072000 |
| 25 | 809559406656000 |
| 26 | 1619118813312000 |
| 27 | 4857356439936000 |