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 | 10 |
| 3 | 102 |
| 4 | 1110 |
| 5 | 10010 |
| 6 | 101010 |
| 7 | 1009470 |
| 8 | 11741730 |
| 9 | 223092870 |
| 10 | 6469693230 |