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 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 3 |
| 6 | 20 |
| 7 | 242 |
| 8 | 6405 |
| 9 | 316835 |
| 10 | 28627261 |
| 11 | 4686329954 |
| 12 | 1382939012729 |
| 13 | 732955581630129 |