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 | -50 |
| 3 | -750 |
| 4 | -13125 |
| 5 | -249375 |
| 6 | -4987500 |
| 7 | -103312500 |
| 8 | -2195390625 |
| 9 | -47566796875 |
| 10 | -1046469531250 |
| 11 | -23307730468750 |
| 12 | -524423935546875 |
| 13 | -11900389306640625 |
| 14 | -272008898437500000 |
| 15 | -6256204664062500000 |
| 16 | -144674732856445312500 |
| 17 | -3361559969311523437500 |