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 | 12 |
| 1 | 252 |
| 2 | 13650 |
| 3 | 1048572 |
| 4 | 91715442 |
| 5 | 8451387252 |
| 6 | 796273301850 |
| 7 | 75771069025932 |
| 8 | 7243289400687522 |
| 9 | 693924501488538852 |
| 10 | 66549379127110766250 |
| 11 | 6385547277321933853692 |
| 12 | 612860534405179485142002 |
| 13 | 58827354670714016735876052 |