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 | 3 |
| 2 | 7 |
| 3 | 18 |
| 4 | 217 |
| 5 | 21586 |
| 6 | 132830816 |
| 7 | 8232750479147118 |
| 8 | 8738244742575919521189548340591 |
| 9 | 28575128242342620144630216663972970082807062570299713849045286 |