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 | 9 |
| 2 | -3996 |
| 3 | -530441 |
| 4 | -16767216 |
| 5 | -244040625 |
| 6 | -2175782336 |
| 7 | -13831287201 |
| 8 | -68619476736 |
| 9 | -281429536481 |
| 10 | -990000000000 |
| 11 | -3038428376721 |
| 12 | -7916100448256 |
| 13 | -13298085122481 |
| 14 | 43306087624704 |
| 15 | 870253662109375 |
| 16 | 9718525023289344 |