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 | 19 |
| 3 | -2561 |
| 4 | 874831 |
| 5 | -319094777 |
| 6 | 47095708213409 |
| 7 | -751163826506551 |
| 8 | 281559662236405100437 |
| 9 | -49061598325832137241324057 |
| 10 | 5012066724315488368700829665081 |
| 11 | -26602063280041700132088988446735433 |
| 12 | 40762630349420684160007591156102493590477 |