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 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 2 |
| 6 | 12 |
| 7 | 12 |
| 8 | 24 |
| 9 | 72 |
| 10 | 720 |
| 11 | 720 |
| 12 | 1440 |
| 13 | 1440 |
| 14 | 10080 |
| 15 | 30240 |
| 16 | 120960 |
| 17 | 120960 |
| 18 | 725760 |
| 19 | 725760 |
| 20 | 7257600 |
| 21 | 7257600 |
| 22 | 79833600 |
| 23 | 79833600 |
| 24 | 958003200 |
| 25 | 4790016000 |
| 26 | 62270208000 |
| 27 | 186810624000 |
| 28 | 2615348736000 |
| 29 | 2615348736000 |
| 30 | 15692092416000 |