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 | 154 |
| 3 | 7173426 |
| 4 | 719542871594973492612 |
| 5 | 725844434877115011240961139425860785107485774851238821757026656 |