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 | 0 |
| 1 | 1 |
| 2 | -7 |
| 3 | 93 |
| 4 | -2159 |
| 5 | 79205 |
| 6 | -4243431 |
| 7 | 313117357 |
| 8 | -30459187423 |
| 9 | 3777547352949 |
| 10 | -581776592603735 |
| 11 | 108932905225448381 |
| 12 | -24370170371013413967 |
| 13 | 6419958293615735090053 |
| 14 | -1967044830254804722091719 |
| 15 | 693575524342402846796188365 |
| 16 | -278846808098157253796358662591 |