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 | 4095 |
| 2 | 262143 |
| 3 | 265720 |
| 4 | 531440 |
| 5 | 1048575 |
| 6 | 5592405 |
| 7 | 11184810 |
| 8 | 122070312 |
| 9 | 183105468 |
| 10 | 193710244 |
| 11 | 244140624 |
| 12 | 268435455 |
| 13 | 387420488 |