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 | -3 |
| 2 | -3 |
| 3 | 0 |
| 4 | -375 |
| 5 | -3993 |
| 6 | 0 |
| 7 | -15265344 |
| 8 | -1343091375 |
| 9 | 0 |
| 10 | -210736858987743 |
| 11 | -141498026224804329 |
| 12 | 0 |
| 13 | -987345386156157037417593 |
| 14 | -4875797582053878382039400448 |
| 15 | 0 |
| 16 | -1562716604740038367719196682456673375 |