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 | -15 |
| 3 | 686 |
| 4 | -62400 |
| 5 | 9406375 |
| 6 | -2117816064 |
| 7 | 665460727820 |
| 8 | -278158506983424 |
| 9 | 149228699913026685 |
| 10 | -99940926131200000000 |
| 11 | 81720620766038589115418 |
| 12 | -80119979953874981093376000 |
| 13 | 92770427931597143858070722691 |
| 14 | -125252587064115948721297529241600 |