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) |
|---|---|
| 0 | 131071 |
| 1 | 66978047 |
| 2 | 2082344719 |
| 3 | 15240409907 |
| 4 | 54033798485 |
| 5 | 90887727786 |
| 6 | 414889199992 |
| 7 | 1654396181398 |
| 8 | 6738967974687 |
| 9 | 26545942883459 |
| 10 | 106105709811500 |
| 11 | 186917937746406 |
| 12 | 847174341792419 |
| 13 | 3387064916515659 |