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 | -1 |
| 3 | -1 |
| 4 | -1 |
| 5 | 0 |
| 6 | 0 |
| 7 | -1 |
| 8 | 1 |
| 9 | 1 |
| 10 | 1 |
| 11 | -1 |
| 12 | 0 |
| 13 | 0 |
| 14 | 0 |
| 15 | -1 |
| 16 | -1 |
| 17 | 1 |
| 18 | 1 |
| 19 | 1 |
| 20 | -1 |
| 21 | 2 |
| 22 | 8 |
| 23 | -18 |
| 24 | -9 |
| 25 | -1 |
| 26 | 4 |
| 27 | 0 |
| 28 | 0 |
| 29 | 0 |
| 30 | 0 |
| 31 | 0 |
| 32 | 0 |
| 33 | 0 |
| 34 | 0 |
| 35 | 0 |
| 36 | -4096 |
| 37 | -4096 |
| 38 | 64 |
| 39 | -20 |
| 40 | -125 |
| 41 | 5 |
| 42 | -6 |
| 43 | -216 |
| 44 | 24 |
| 45 | 152 |
| 46 | 54872 |
| 47 | -106742 |
| 48 | 14045 |
| 49 | 125 |
| 50 | -21125 |
| 51 | -274625 |
| 52 | -274625 |
| 53 | 10985 |
| 54 | -16731 |
| 55 | -970299 |
| 56 | 1804275 |
| 57 | 1312200 |
| 58 | 373248 |
| 59 | -691488 |
| 60 | -192080 |