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 | 6 |
| 5 | 12 |
| 6 | 36 |
| 7 | 120 |
| 8 | 240 |
| 9 | 720 |
| 10 | 2520 |
| 11 | 10080 |
| 12 | 30240 |
| 13 | 110880 |
| 14 | 443520 |
| 15 | 1814400 |
| 16 | 6652800 |
| 17 | 26611200 |
| 18 | 133056000 |
| 19 | 518918400 |
| 20 | 2075673600 |
| 21 | 10378368000 |
| 22 | 58118860800 |
| 23 | 261534873600 |
| 24 | 1270312243200 |
| 25 | 5928123801600 |
| 26 | 29640619008000 |
| 27 | 168951528345600 |
| 28 | 844757641728000 |
| 29 | 4505374089216000 |
| 30 | 25342729251840000 |