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) |
|---|---|
| 1 | 4 |
| 2 | 9 |
| 3 | 64 |
| 4 | 900 |
| 5 | 20736 |
| 6 | 705600 |
| 7 | 33177600 |
| 8 | 2057529600 |
| 9 | 162570240000 |
| 10 | 15933509222400 |
| 11 | 1896219279360000 |
| 12 | 269276305858560000 |
| 13 | 44970736429301760000 |
| 14 | 8724552309817344000000 |
| 15 | 1945613940877311344640000 |