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 | 24 |
| 2 | 936 |
| 3 | 42798 |
| 4 | 2130456 |
| 5 | 111557592 |
| 6 | 6041272680 |
| 7 | 335089258632 |
| 8 | 18922687509960 |
| 9 | 1083572842675608 |
| 10 | 62744027461625646 |
| 11 | 3666433604712457464 |
| 12 | 215879610645469496232 |
| 13 | 12792865816027823374872 |
| 14 | 762278349313657804740840 |
| 15 | 45638342462133835019322552 |