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 | -24 |
| 2 | 312 |
| 3 | -2912 |
| 4 | 21816 |
| 5 | -139152 |
| 6 | 783328 |
| 7 | -3986112 |
| 8 | 18650424 |
| 9 | -81251896 |
| 10 | 332798544 |
| 11 | -1291339296 |
| 12 | 4776117216 |
| 13 | -16922753616 |
| 14 | 57683178432 |
| 15 | -189821722688 |
| 16 | 604884735288 |
| 17 | -1871370360240 |
| 18 | 5633654421720 |