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 | 4 |
| 2 | 15 |
| 3 | 255 |
| 4 | 5865 |
| 5 | 170085 |
| 6 | 5437705 |
| 7 | 226473065 |
| 8 | 10380578845 |
| 9 | 494390700895 |
| 10 | 43592479037107 |