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 | 1 |
| 2 | 3 |
| 3 | 15 |
| 4 | 135 |
| 5 | 2295 |
| 6 | 75735 |
| 7 | 4922775 |
| 8 | 635037975 |
| 9 | 163204759575 |
| 10 | 83724041661975 |
| 11 | 85817142703524375 |
| 12 | 175839325399521444375 |
| 13 | 720413716161839357604375 |
| 14 | 5902349576513949856852644375 |
| 15 | 96709997811181068404530578084375 |