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 | 3 |
| 4 | -2 |
| 5 | -9 |
| 6 | 15 |
| 7 | -4 |
| 8 | -18 |
| 9 | -25 |
| 10 | 55 |
| 11 | -8 |
| 12 | -36 |
| 13 | -50 |
| 14 | -121 |
| 15 | 231 |
| 16 | -16 |
| 17 | -72 |
| 18 | -100 |
| 19 | -242 |
| 20 | -441 |
| 21 | 903 |
| 22 | -32 |
| 23 | -144 |
| 24 | -200 |
| 25 | -484 |
| 26 | -882 |
| 27 | -1849 |
| 28 | 3655 |
| 29 | -64 |
| 30 | -288 |
| 31 | -400 |
| 32 | -968 |
| 33 | -1764 |
| 34 | -3698 |
| 35 | -7225 |
| 36 | 14535 |
| 37 | -128 |
| 38 | -576 |
| 39 | -800 |
| 40 | -1936 |
| 41 | -3528 |
| 42 | -7396 |
| 43 | -14450 |
| 44 | -29241 |
| 45 | 58311 |
| 46 | -256 |
| 47 | -1152 |
| 48 | -1600 |
| 49 | -3872 |
| 50 | -7056 |
| 51 | -14792 |
| 52 | -28900 |
| 53 | -58482 |
| 54 | -116281 |
| 55 | 232903 |