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 | 15 |
| 2 | 207 |
| 3 | 1023 |
| 4 | 2975 |
| 5 | 19359 |
| 6 | 147455 |
| 7 | 1207359 |
| 8 | 5017599 |
| 9 | 2170814463 |
| 10 | 58946212863 |
| 11 | 1166333691001023 |
| 12 | 36472996363223648799 |