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 | 6 |
| 2 | 12 |
| 3 | 18 |
| 4 | 66 |
| 5 | 180 |
| 6 | 1596 |
| 7 | 2700 |
| 8 | 4098 |
| 9 | 30594 |
| 10 | 65538 |