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 | -3 |
| 3 | -8 |
| 4 | 15 |
| 5 | -91 |
| 6 | -54 |
| 7 | 2531 |
| 8 | -17021 |
| 9 | 43035 |
| 10 | -66258 |
| 11 | 1958757 |
| 12 | -24572453 |
| 13 | 146991979 |
| 14 | -287482322 |
| 15 | -3148566077 |
| 16 | 35506973089 |
| 17 | -198639977241 |
| 18 | 1006345648929 |
| 19 | -8250266425561 |
| 20 | 76832268802555 |
| 21 | -517564939540551 |
| 22 | 1890772860334557 |
| 23 | 3323588929061820 |
| 24 | -104547561696315008 |
| 25 | 907385094824827328 |
| 26 | -6313246535826877248 |