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 | -16 |
| 2 | 128 |
| 3 | -704 |
| 4 | 3072 |
| 5 | -11488 |
| 6 | 38400 |
| 7 | -117632 |
| 8 | 335872 |
| 9 | -904784 |
| 10 | 2320128 |
| 11 | -5702208 |
| 12 | 13504512 |
| 13 | -30952544 |
| 14 | 68901888 |
| 15 | -149403264 |
| 16 | 316342272 |
| 17 | -655445792 |
| 18 | 1331327616 |
| 19 | -2655115712 |
| 20 | 5206288384 |
| 21 | -10049485312 |
| 22 | 19115905536 |
| 23 | -35867019904 |
| 24 | 66437873664 |