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) |
|---|---|
| 4 | 1 |
| 5 | 2 |
| 6 | 23 |
| 7 | 415 |
| 8 | 19041 |
| 9 | 1104045 |
| 10 | 79818336 |
| 11 | 6958257941 |
| 12 | 720814138673 |
| 13 | 87579097910309 |