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 | -26 |
| 2 | 364 |
| 3 | -3640 |
| 4 | 29094 |
| 5 | -197288 |
| 6 | 1177176 |
| 7 | -6333184 |
| 8 | 31258604 |
| 9 | -143374530 |
| 10 | 617193304 |
| 11 | -2513060264 |
| 12 | 9739727816 |
| 13 | -36115518376 |
| 14 | 128680223152 |
| 15 | -442158402816 |
| 16 | 1469734751654 |
| 17 | -4738671343952 |
| 18 | 14853923411652 |