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 | 11 |
| 3 | 28 |
| 4 | -1547 |
| 5 | -980 |
| 6 | 133691 |
| 7 | 81172 |
| 8 | -10955627 |
| 9 | -11878244 |
| 10 | 4448226055 |
| 11 | 2674671076 |
| 12 | -49823872362737 |
| 13 | -855605816468 |
| 14 | 40888881655517 |
| 15 | 368601472639540 |
| 16 | -1711418530905680779 |
| 17 | -205700802920736452 |
| 18 | 1681258656184674505817 |
| 19 | 144338957346266943364 |