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 | 0 |
| 2 | 8190 |
| 3 | 698880 |
| 4 | -754790400 |
| 5 | -131455134720 |
| 6 | 90235527782400 |
| 7 | 25034722952279040 |
| 8 | -11631379080860106750 |
| 9 | -4740180695347850188800 |
| 10 | 1500620323887236434821120 |
| 11 | 888527739621938585682240000 |
| 12 | -181995668700704689414022799360 |
| 13 | -164466129435036361896228722795520 |