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 | 2 |
| 3 | 12 |
| 4 | -21 |
| 5 | 4 |
| 6 | 36 |
| 7 | -68 |
| 8 | 21 |
| 9 | 112 |
| 10 | -184 |
| 11 | 44 |
| 12 | 275 |
| 13 | -456 |
| 14 | 112 |
| 15 | 644 |
| 16 | -1019 |
| 17 | 240 |
| 18 | 1370 |
| 19 | -2156 |
| 20 | 514 |
| 21 | 2828 |
| 22 | -4340 |
| 23 | 992 |
| 24 | 5498 |
| 25 | -8392 |
| 26 | 1930 |
| 27 | 10428 |
| 28 | -15675 |
| 29 | 3528 |
| 30 | 19060 |
| 31 | -28472 |
| 32 | 6399 |
| 33 | 34072 |
| 34 | -50382 |
| 35 | 11184 |
| 36 | 59333 |
| 37 | -87260 |
| 38 | 19312 |
| 39 | 101496 |
| 40 | -148148 |
| 41 | 32480 |
| 42 | 170130 |
| 43 | -247156 |