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 | -3 |
| 2 | 36 |
| 3 | -189 |
| 4 | 567 |
| 5 | -2430 |
| 6 | 9477 |
| 7 | -28431 |
| 8 | 104976 |
| 9 | -373977 |
| 10 | 1121931 |
| 11 | -3897234 |
| 12 | 13286025 |
| 13 | -39858075 |
| 14 | 133923132 |
| 15 | -444816117 |
| 16 | 1334448351 |
| 17 | -4390765542 |
| 18 | 14334558093 |
| 19 | -43003674279 |
| 20 | 139471376040 |
| 21 | -449795187729 |
| 22 | 1349385563187 |
| 23 | -4330586226042 |
| 24 | 13839047287569 |