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 | 2 |
| 2 | 1 |
| 3 | 8 |
| 4 | 7 |
| 5 | 134 |
| 6 | 37 |
| 7 | 8516 |
| 8 | 12259 |
| 9 | 2196098 |
| 10 | -1896671 |
| 11 | 2242814912 |
| 12 | 8371908703 |
| 13 | 9201070882046 |
| 14 | -50188906239587 |
| 15 | 150640766448080444 |
| 16 | 1945921801461187291 |
| 17 | 9876134472777874272122 |
| 18 | -235305539337366453248999 |