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 | 2 |
| 3 | 2 |
| 4 | 4 |
| 5 | 8 |
| 6 | 32 |
| 7 | 184 |
| 8 | 15392 |
| 9 | 5400584 |
| 10 | 74651892640 |
| 11 | 25003708306137848 |
| 12 | 6335942056759761366725617280 |
| 13 | 20682199297864337408779128828731176793076928 |