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 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | -4914 |
| 7 | -181854 |
| 8 | -4339944 |
| 9 | -89153184 |
| 10 | -1746815574 |
| 11 | -33850986114 |
| 12 | -655203251304 |
| 13 | -12686085675144 |
| 14 | -245683477042884 |
| 15 | -4758284508073524 |
| 16 | -92156792465163564 |
| 17 | -1784855834560787004 |
| 18 | -34568319709081645344 |
| 19 | -669504074781304567584 |
| 20 | -12966661247726595160224 |