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 | 1 |
| 4 | -2 |
| 5 | 1 |
| 6 | 1 |
| 7 | -4 |
| 8 | 5 |
| 9 | -2 |
| 10 | 1 |
| 11 | -7 |
| 12 | 17 |
| 13 | -17 |
| 14 | 6 |
| 15 | 1 |
| 16 | -11 |
| 17 | 45 |
| 18 | -85 |
| 19 | 74 |
| 20 | -24 |
| 21 | 1 |
| 22 | -16 |
| 23 | 100 |
| 24 | -310 |
| 25 | 499 |
| 26 | -394 |
| 27 | 120 |
| 28 | 1 |
| 29 | -22 |
| 30 | 196 |
| 31 | -910 |
| 32 | 2359 |
| 33 | -3388 |
| 34 | 2484 |
| 35 | -720 |
| 36 | 1 |
| 37 | -29 |
| 38 | 350 |
| 39 | -2282 |
| 40 | 8729 |
| 41 | -19901 |
| 42 | 26200 |
| 43 | -18108 |
| 44 | 5040 |
| 45 | 1 |
| 46 | -37 |
| 47 | 582 |
| 48 | -5082 |
| 49 | 26985 |
| 50 | -89733 |
| 51 | 185408 |