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 | 3 |
| 2 | 5 |
| 3 | 127 |
| 4 | 3299 |
| 5 | 1967249047 |
| 6 | 8191 |
| 7 | 30450469261 |
| 8 | 131071 |
| 9 | 524287 |
| 10 | 476562280296181 |
| 11 | 70358283824461 |