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 | -4 |
| 2 | 12 |
| 3 | -24 |
| 4 | 36 |
| 5 | -36 |
| 6 | 8 |
| 7 | 56 |
| 8 | -148 |
| 9 | 228 |
| 10 | -228 |
| 11 | 80 |
| 12 | 248 |
| 13 | -688 |
| 14 | 1048 |
| 15 | -1048 |
| 16 | 420 |
| 17 | 896 |
| 18 | -2588 |
| 19 | 3920 |
| 20 | -3884 |
| 21 | 1648 |
| 22 | 2864 |
| 23 | -8488 |
| 24 | 12744 |
| 25 | -12516 |
| 26 | 5440 |
| 27 | 8400 |
| 28 | -25176 |
| 29 | 37480 |
| 30 | -36504 |
| 31 | 16032 |
| 32 | 22892 |
| 33 | -69024 |
| 34 | 101968 |
| 35 | -98504 |
| 36 | 43468 |
| 37 | 58736 |
| 38 | -177584 |
| 39 | 260416 |
| 40 | -249732 |
| 41 | 110328 |