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 | 26 |
| 4 | -189 |
| 5 | 1479 |
| 6 | -12106 |
| 7 | 102224 |
| 8 | -883031 |
| 9 | 7761209 |
| 10 | -69153920 |
| 11 | 623018880 |
| 12 | -5664270185 |
| 13 | 51892998965 |
| 14 | -478521450110 |
| 15 | 4437418074830 |
| 16 | -41350439060725 |
| 17 | 386983852716405 |