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) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 5 |
| 5 | 16 |
| 6 | 75 |
| 7 | 544 |
| 8 | 6920 |
| 9 | 159228 |
| 10 | 6961507 |
| 11 | 577826609 |
| 12 | 90529308665 |