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 | 521 |
| 2 | 11293772630057337854244300009061892827351888021 |
| 3 | 6573840876841765045097738044023218580610053625908525039752324422200521 |
| 4 | 164346021921044126127443451100580464515251340647713125993808110555013021 |