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 | -14 |
| 3 | 115 |
| 4 | -800 |
| 5 | 5125 |
| 6 | -31250 |
| 7 | 184375 |
| 8 | -1062500 |
| 9 | 6015625 |
| 10 | -33593750 |
| 11 | 185546875 |
| 12 | -1015625000 |
| 13 | 5517578125 |
| 14 | -29785156250 |
| 15 | 159912109375 |
| 16 | -854492187500 |
| 17 | 4547119140625 |
| 18 | -24108886718750 |
| 19 | 127410888671875 |
| 20 | -671386718750000 |