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 | 3 |
| 3 | 9 |
| 4 | 37 |
| 5 | 111 |
| 6 | 333 |
| 7 | 333667 |
| 8 | 1001001 |
| 9 | 3003003 |
| 10 | 12345679 |
| 11 | 37037037 |
| 12 | 111111111 |