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 | 1 |
| 2 | -3 |
| 3 | -5 |
| 4 | -22 |
| 5 | -141 |
| 6 | 719 |
| 7 | 8765 |
| 8 | 14319 |
| 9 | 1707596 |
| 10 | -21672017 |
| 11 | -962616165 |
| 12 | 16392942967 |
| 13 | -1419903481091 |
| 14 | 100267906812546 |
| 15 | 7990790144939605 |
| 16 | -1147738310571578779 |
| 17 | 53860607055523082151 |
| 18 | -43705893899966302362943 |