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 | 1 |
| 1 | -5 |
| 2 | 275 |
| 3 | -302250 |
| 4 | 6175682500 |
| 5 | -2459739648441250 |
| 6 | 20152832471795703093750 |
| 7 | -3521676074865217676579415546875 |
| 8 | 13442076416943428772681311252971648437500 |