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) |
|---|---|
| 2 | -1 |
| 3 | 41 |
| 4 | -7843 |
| 5 | 252769 |
| 6 | -69838386 |
| 7 | 32793164357 |
| 8 | -1610849246753 |
| 9 | 3511931460657095 |
| 10 | -16239361950453107572 |
| 11 | 8129795565691811281818 |
| 12 | -22648638361771185452289570 |
| 13 | 3264253036763451979723532099 |