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 | 3465253618401 |
| 2 | 44202753561285411 |
| 3 | 1640293473202755801 |
| 4 | 10623546148468360251 |