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 | -8 |
| 2 | 24 |
| 3 | -72 |
| 4 | 344 |
| 5 | -1416 |
| 6 | 5400 |
| 7 | -21576 |
| 8 | 87000 |
| 9 | -348296 |
| 10 | 1390872 |
| 11 | -5560776 |
| 12 | 22253784 |
| 13 | -89025672 |
| 14 | 356055960 |
| 15 | -1424186568 |
| 16 | 5696931032 |
| 17 | -22787865096 |
| 18 | 91150729368 |
| 19 | -364602357960 |
| 20 | 1458412314456 |
| 21 | -5833651510536 |
| 22 | 23334594559128 |
| 23 | -93338369011272 |
| 24 | 373353522099288 |