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) |
|---|---|
| 1 | 1 |
| 2 | 0 |
| 3 | 3 |
| 4 | -5 |
| 5 | 6 |
| 6 | -3 |
| 7 | 14 |
| 8 | -48 |
| 9 | 52 |
| 10 | -10 |
| 11 | 90 |
| 12 | -329 |
| 13 | 234 |
| 14 | -28 |
| 15 | 1038 |
| 16 | -2349 |
| 17 | 1598 |
| 18 | -1044 |
| 19 | 4182 |
| 20 | -12750 |
| 21 | 17262 |
| 22 | -198 |
| 23 | 28658 |
| 24 | -135285 |
| 25 | 90031 |
| 26 | -520 |
| 27 | 300405 |
| 28 | -554974 |
| 29 | 514230 |
| 30 | -464658 |
| 31 | 1346270 |
| 32 | -5188656 |
| 33 | 5326470 |
| 34 | -3570 |
| 35 | 11782764 |
| 36 | -34556612 |
| 37 | 24157818 |
| 38 | -9348 |
| 39 | 95140422 |
| 40 | -256249218 |
| 41 | 165580142 |