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 | 0 |
| 3 | -2 |
| 4 | 1 |
| 5 | 0 |
| 6 | 4 |
| 7 | -2 |
| 8 | 0 |
| 9 | -6 |
| 10 | 4 |
| 11 | 0 |
| 12 | 10 |
| 13 | -6 |
| 14 | 0 |
| 15 | -16 |
| 16 | 9 |
| 17 | 0 |
| 18 | 24 |
| 19 | -14 |
| 20 | 0 |
| 21 | -36 |
| 22 | 20 |
| 23 | 0 |
| 24 | 52 |
| 25 | -29 |
| 26 | 0 |
| 27 | -74 |
| 28 | 42 |
| 29 | 0 |
| 30 | 104 |
| 31 | -58 |
| 32 | 0 |
| 33 | -144 |
| 34 | 80 |
| 35 | 0 |
| 36 | 198 |
| 37 | -110 |
| 38 | 0 |
| 39 | -268 |
| 40 | 148 |
| 41 | 0 |
| 42 | 360 |
| 43 | -198 |
| 44 | 0 |
| 45 | -480 |
| 46 | 264 |
| 47 | 0 |
| 48 | 634 |
| 49 | -347 |
| 50 | 0 |
| 51 | -832 |
| 52 | 454 |
| 53 | 0 |
| 54 | 1084 |
| 55 | -592 |
| 56 | 0 |
| 57 | -1404 |
| 58 | 764 |
| 59 | 0 |
| 60 | 1808 |
| 61 | -982 |