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 | 0 |
| 2 | -1 |
| 3 | 1 |
| 4 | -2 |
| 5 | 1 |
| 6 | 0 |
| 7 | -9 |
| 8 | 6 |
| 9 | -1 |
| 10 | 1 |
| 11 | -12 |
| 12 | 38 |
| 13 | -12 |
| 14 | 1 |
| 15 | 0 |
| 16 | -25 |
| 17 | 100 |
| 18 | -110 |
| 19 | 20 |
| 20 | -1 |
| 21 | 1 |
| 22 | -30 |
| 23 | 255 |
| 24 | -452 |
| 25 | 255 |
| 26 | -30 |
| 27 | 1 |
| 28 | 0 |
| 29 | -49 |
| 30 | 490 |
| 31 | -1519 |
| 32 | 1484 |
| 33 | -511 |
| 34 | 42 |
| 35 | -1 |
| 36 | 1 |
| 37 | -56 |
| 38 | 924 |
| 39 | -3976 |
| 40 | 6470 |
| 41 | -3976 |
| 42 | 924 |
| 43 | -56 |
| 44 | 1 |
| 45 | 0 |
| 46 | -81 |
| 47 | 1512 |
| 48 | -9324 |
| 49 | 21816 |
| 50 | -21942 |
| 51 | 9240 |
| 52 | -1548 |
| 53 | 72 |
| 54 | -1 |
| 55 | 1 |
| 56 | -90 |