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 | -1 |
| 5 | 3 |
| 6 | -3 |
| 7 | -1 |
| 8 | 7 |
| 9 | -9 |
| 10 | 5 |
| 11 | -1 |
| 12 | -7 |
| 13 | 25 |
| 14 | -27 |
| 15 | -3 |
| 16 | 29 |
| 17 | -41 |
| 18 | 55 |
| 19 | -25 |
| 20 | -73 |
| 21 | 161 |
| 22 | -143 |
| 23 | -11 |
| 24 | 217 |
| 25 | -387 |
| 26 | 447 |
| 27 | -99 |
| 28 | -737 |
| 29 | 1377 |
| 30 | -1219 |
| 31 | 209 |
| 32 | 1761 |
| 33 | -3999 |
| 34 | 4357 |
| 35 | -1087 |
| 36 | -5311 |
| 37 | 11463 |
| 38 | -12475 |
| 39 | 4723 |
| 40 | 12705 |
| 41 | -33133 |
| 42 | 38839 |
| 43 | -15005 |
| 44 | -35001 |
| 45 | 90485 |
| 46 | -112395 |
| 47 | 54269 |
| 48 | 92435 |
| 49 | -262555 |
| 50 | 328759 |
| 51 | -165839 |
| 52 | -244533 |