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 | 6 |
| 3 | 30 |
| 4 | 105 |
| 5 | 210 |
| 6 | 2310 |
| 7 | 15015 |
| 8 | 30030 |
| 9 | 255255 |
| 10 | 510510 |
| 11 | 1939938 |
| 12 | 3233230 |
| 13 | 4849845 |
| 14 | 9699690 |
| 15 | 111546435 |
| 16 | 223092870 |
| 17 | 3234846615 |
| 18 | 6469693230 |