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 | -12 |
| 2 | -108 |
| 3 | -1344 |
| 4 | -22044 |
| 5 | -409752 |
| 6 | -8201088 |
| 7 | -172293504 |
| 8 | -3746915388 |
| 9 | -83625518604 |
| 10 | -1904468689368 |
| 11 | -44079484775616 |
| 12 | -1033852665619200 |
| 13 | -24518163456010392 |
| 14 | -586936016770722048 |
| 15 | -14164129272396668544 |
| 16 | -344209494372831399036 |