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) |
|---|---|
| 1 | 1 |
| 2 | -4 |
| 3 | 12 |
| 4 | -32 |
| 5 | 78 |
| 6 | -176 |
| 7 | 376 |
| 8 | -768 |
| 9 | 1509 |
| 10 | -2872 |
| 11 | 5316 |
| 12 | -9600 |
| 13 | 16966 |
| 14 | -29408 |
| 15 | 50088 |
| 16 | -83968 |
| 17 | 138738 |
| 18 | -226196 |
| 19 | 364284 |
| 20 | -580032 |
| 21 | 913824 |
| 22 | -1425552 |
| 23 | 2203368 |
| 24 | -3376128 |
| 25 | 5130999 |
| 26 | -7738136 |
| 27 | 11585208 |
| 28 | -17225472 |
| 29 | 25444278 |
| 30 | -37350816 |
| 31 | 54504160 |
| 32 | -79085568 |
| 33 | 114133296 |