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 | 0 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 3 |
| 5 | 212 |
| 6 | 10592 |
| 7 | 449977 |
| 8 | 17727425 |
| 9 | 680781219 |
| 10 | 26046238416 |
| 11 | 1001222256515 |
| 12 | 38764377926857 |
| 13 | 1511202832516487 |