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 | 1 |
| 2 | 9 |
| 3 | 100 |
| 4 | 1225 |
| 5 | 15876 |
| 6 | 213444 |
| 7 | 2944656 |
| 8 | 41409225 |
| 9 | 590976100 |
| 10 | 8533694884 |
| 11 | 124408576656 |
| 12 | 1828114918084 |
| 13 | 27043120090000 |
| 14 | 402335398890000 |
| 15 | 6015361252737600 |
| 16 | 90324408810638025 |
| 17 | 1361429497505672100 |
| 18 | 20589520178326522500 |
| 19 | 312321918272897610000 |