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 | 13 |
| 2 | 271 |
| 3 | 28284463 |
| 4 | 12610431355437389859745050577282818321295774208230808159 |
| 5 | 421002806942919116087256468214897259565893934905313644799059599 |