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 | -5 |
| 3 | 11 |
| 4 | -125 |
| 5 | 1054 |
| 6 | -209 |
| 7 | -15625 |
| 8 | 14035 |
| 9 | -130525 |
| 10 | 1899830 |
| 11 | -134905 |
| 12 | -25499225 |
| 13 | -64447293 |
| 14 | -133867445 |
| 15 | 6309965146 |
| 16 | -11762712973 |
| 17 | -29646853725 |
| 18 | -160561408097 |
| 19 | -1495301415045 |
| 20 | 24032249395590 |
| 21 | -42497223256645 |
| 22 | -176218120143125 |
| 23 | 271151209742715 |
| 24 | -6483574667232425 |