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 | -7 |
| 2 | 121 |
| 3 | -2439 |
| 4 | 54905 |
| 5 | -1321351 |
| 6 | 33281657 |
| 7 | -866396551 |
| 8 | 23125022329 |
| 9 | -629441571207 |
| 10 | 17405126104697 |
| 11 | -487562768820615 |
| 12 | 13806913025988217 |
| 13 | -394606681111406983 |
| 14 | 11367704830045574777 |
| 15 | -329739328993506896263 |
| 16 | 9622560010799553435257 |