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 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 2687088 |
| 6 | 79355392 |
| 7 | 1008580720 |
| 8 | 7955368960 |
| 9 | 55993694000 |
| 10 | 284540909568 |
| 11 | 1291577484720 |
| 12 | 4756123165696 |