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 | 3 |
| 2 | 15 |
| 3 | 75 |
| 4 | 525 |
| 5 | 5775 |
| 6 | 75075 |
| 7 | 1276275 |
| 8 | 24249225 |
| 9 | 703227525 |
| 10 | 21800053275 |
| 11 | 893802184275 |
| 12 | 38433493923825 |
| 13 | 2267576141505675 |
| 14 | 138322144631846175 |
| 15 | 9820872268861078425 |
| 16 | 716923675626858725025 |
| 17 | 72409291238312731227525 |