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 | -3 |
| 2 | -13 |
| 3 | 333 |
| 4 | 2717 |
| 5 | -131043 |
| 6 | -1599793 |
| 7 | 109190253 |
| 8 | 1777008857 |
| 9 | -156107958723 |
| 10 | -3175649491573 |
| 11 | 341011318885773 |
| 12 | 8324471625279797 |
| 13 | -1056450457249168803 |
| 14 | -30087334294452702553 |
| 15 | 4405799115103013278893 |
| 16 | 143400677661526320767537 |
| 17 | -23798518054913516311313283 |