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 | 2 |
| 2 | 6 |
| 3 | 30 |
| 4 | 210 |
| 5 | 15810 |
| 6 | 292110 |
| 7 | 16893030 |
| 8 | 984016110 |
| 9 | 17088913842 |
| 10 | 2446241358990 |
| 11 | 1098013758964122 |