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 | -6 |
| 2 | 27 |
| 3 | -92 |
| 4 | 279 |
| 5 | -756 |
| 6 | 1913 |
| 7 | -4536 |
| 8 | 10260 |
| 9 | -22220 |
| 10 | 46479 |
| 11 | -94176 |
| 12 | 185749 |
| 13 | -357426 |
| 14 | 673056 |
| 15 | -1242404 |
| 16 | 2252772 |
| 17 | -4017816 |
| 18 | 7058609 |
| 19 | -12228060 |
| 20 | 20911230 |
| 21 | -35330324 |
| 22 | 59023728 |
| 23 | -97568712 |
| 24 | 159693831 |
| 25 | -258941124 |
| 26 | 416181510 |
| 27 | -663337512 |
| 28 | 1048935414 |
| 29 | -1646245836 |