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 | 25 |
| 2 | 600 |
| 3 | 14400 |
| 4 | 345300 |
| 5 | 8280000 |
| 6 | 198547500 |
| 7 | 4761000000 |
| 8 | 114164729700 |
| 9 | 2737573095600 |
| 10 | 65644673871900 |
| 11 | 1574103433035600 |
| 12 | 37745661174674100 |
| 13 | 905108843301991200 |
| 14 | 21703740051934476300 |
| 15 | 520437222249938431200 |