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 | 0 |
| 1 | 1 |
| 2 | -125 |
| 3 | 249250 |
| 4 | -2886735625 |
| 5 | 122209131374375 |
| 6 | -14455143383196875000 |
| 7 | 4006210678487307667578125 |
| 8 | -2297417123000769120910212890625 |
| 9 | 2485076260705905645263720799941406250 |
| 10 | -4719878705811419698488114573981055908203125 |