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 | 20 |
| 4 | 52 |
| 5 | 156 |
| 6 | 768 |
| 7 | 8244 |
| 8 | 25808 |
| 9 | 406764 |
| 10 | 3610688 |
| 11 | 41395016 |
| 12 | 453695175 |
| 13 | 3325792768 |