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 | 2 |
| 2 | 10 |
| 3 | 3386897 |
| 4 | 10367022 |
| 5 | 25898098514 |
| 6 | 33868444120607410 |
| 7 | 3835970218282143377 |