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 | 6 |
| 4 | 14 |
| 5 | 22 |
| 6 | 252 |
| 7 | 17526 |
| 8 | 9278038 |
| 9 | 23694308 |
| 10 | 1186593143406 |
| 11 | 789632365568454684 |
| 12 | 3199548374111958458274 |
| 13 | 849440501364681630324594977448 |