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 | 24 |
| 3 | 624 |
| 4 | 9375 |
| 5 | 90624 |
| 6 | 890624 |
| 7 | 7109375 |
| 8 | 12890624 |
| 9 | 212890624 |
| 10 | 1787109375 |
| 11 | 81787109375 |
| 12 | 81787109375 |
| 13 | 81787109375 |
| 14 | 59918212890624 |
| 15 | 259918212890624 |
| 16 | 3740081787109375 |
| 17 | 56259918212890624 |
| 18 | 256259918212890624 |
| 19 | 7743740081787109375 |
| 20 | 7743740081787109375 |