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 | -1 |
| 2 | -1 |
| 3 | 2 |
| 4 | -1 |
| 5 | -2 |
| 6 | 4 |
| 7 | -2 |
| 8 | -4 |
| 9 | 8 |
| 10 | -4 |
| 11 | -7 |
| 12 | 14 |
| 13 | -6 |
| 14 | -13 |
| 15 | 24 |
| 16 | -10 |
| 17 | -21 |
| 18 | 40 |
| 19 | -17 |
| 20 | -35 |
| 21 | 63 |
| 22 | -26 |
| 23 | -55 |
| 24 | 98 |
| 25 | -40 |
| 26 | -84 |
| 27 | 150 |
| 28 | -61 |
| 29 | -127 |
| 30 | 224 |
| 31 | -90 |
| 32 | -189 |
| 33 | 330 |
| 34 | -131 |
| 35 | -275 |
| 36 | 480 |
| 37 | -190 |
| 38 | -397 |
| 39 | 687 |
| 40 | -270 |
| 41 | -565 |
| 42 | 974 |
| 43 | -381 |
| 44 | -795 |
| 45 | 1367 |
| 46 | -533 |
| 47 | -1109 |
| 48 | 1898 |
| 49 | -737 |
| 50 | -1533 |
| 51 | 2614 |