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) |
|---|---|
| 0 | 1 |
| 1 | -2 |
| 2 | 12 |
| 3 | -128 |
| 4 | 1872 |
| 5 | -37600 |
| 6 | 990784 |
| 7 | -32333824 |
| 8 | 1272660224 |
| 9 | -59527313920 |
| 10 | 3252626013184 |
| 11 | -204354574172160 |
| 12 | 14594815769038848 |
| 13 | -1174376539738169344 |
| 14 | 105595092426069327872 |
| 15 | -10530693390637550272512 |