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) |
|---|---|
| 3 | 1 |
| 4 | -300 |
| 5 | 105050 |
| 6 | -35927100 |
| 7 | 12328144851 |
| 8 | -4228301370600 |
| 9 | 1450319733570100 |
| 10 | -497459062806004200 |
| 11 | 170628488227082949701 |
| 12 | -58525570007342935110900 |
| 13 | 20074270583791406305395150 |
| 14 | -6885474806748086165925231300 |