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 | -11 |
| 2 | 47 |
| 3 | -55 |
| 4 | -1187 |
| 5 | 935 |
| 6 | 134447 |
| 7 | -81235 |
| 8 | -10954907 |
| 9 | 11878163 |
| 10 | 4448228035 |
| 11 | -2674671175 |
| 12 | -49823872264457 |
| 13 | 855605816351 |
| 14 | 40888881655769 |
| 15 | -368601472639675 |
| 16 | -1711418530905656299 |
| 17 | 205700802920736299 |
| 18 | 1681258656184674548909 |
| 19 | -144338957346266943535 |