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 | 4 |
| 3 | -263 |
| 4 | 181 |
| 5 | -19417 |
| 6 | 2650183 |
| 7 | -334415182 |
| 8 | 2505796264 |
| 9 | -1075533383968 |
| 10 | 644250947168711 |
| 11 | -35934792935656882 |
| 12 | 59703596150692742866 |
| 13 | -2784264154855168826899 |
| 14 | 13245106337447512956269 |
| 15 | 145404446885533849363819862 |
| 16 | -576405412549008975387674250194 |