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 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 4 |
| 5 | 0 |
| 6 | 0 |
| 7 | 0 |
| 8 | -8 |
| 9 | 0 |
| 10 | 112 |
| 11 | -256 |
| 12 | 156 |
| 13 | 896 |
| 14 | -3536 |
| 15 | 5472 |
| 16 | 5400 |
| 17 | -49088 |
| 18 | 115008 |
| 19 | -47776 |
| 20 | -555492 |
| 21 | 1976736 |
| 22 | -2563424 |
| 23 | -4446272 |
| 24 | 29452776 |
| 25 | -61952896 |
| 26 | 4795392 |
| 27 | 374024448 |
| 28 | -1173895476 |