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 | 4 |
| 2 | -322 |
| 3 | -3992 |
| 4 | 310540 |
| 5 | 6639344 |
| 6 | -498255224 |
| 7 | -15457610528 |
| 8 | 1117041417872 |
| 9 | 46265544539200 |
| 10 | -3212977815009824 |
| 11 | -169229451802535296 |
| 12 | 11268933708996384448 |
| 13 | 731470391347068698368 |
| 14 | -46589813151941838471040 |
| 15 | -3647677144462096434561536 |
| 16 | 221619644102496735309926656 |