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 | 16383 |
| 3 | 10450787266 |
| 4 | 71832238695530495 |
| 5 | 2891333179750701904296876 |
| 6 | 475997448692406224810330915906802 |
| 7 | 252848108054080530934326716965286554552380 |