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 | 1 |
| 2 | 4 |
| 3 | 45 |
| 4 | 1017 |
| 5 | 50949 |
| 6 | 4988145 |
| 7 | 1073114625 |
| 8 | 456837553545 |
| 9 | 427500156271073 |
| 10 | 794420496019076757 |
| 11 | 3247016064162495298253 |