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 | -2 |
| 2 | 1 |
| 3 | -2 |
| 4 | 4 |
| 5 | -4 |
| 6 | 5 |
| 7 | -6 |
| 8 | 9 |
| 9 | -12 |
| 10 | 13 |
| 11 | -16 |
| 12 | 21 |
| 13 | -26 |
| 14 | 29 |
| 15 | -36 |
| 16 | 46 |
| 17 | -54 |
| 18 | 62 |
| 19 | -74 |
| 20 | 90 |
| 21 | -106 |
| 22 | 122 |
| 23 | -142 |
| 24 | 171 |
| 25 | -200 |
| 26 | 227 |
| 27 | -264 |
| 28 | 311 |
| 29 | -358 |
| 30 | 408 |
| 31 | -470 |
| 32 | 545 |
| 33 | -626 |
| 34 | 709 |
| 35 | -810 |
| 36 | 933 |
| 37 | -1062 |
| 38 | 1198 |
| 39 | -1362 |
| 40 | 1555 |
| 41 | -1760 |
| 42 | 1980 |
| 43 | -2238 |
| 44 | 2536 |
| 45 | -2858 |
| 46 | 3205 |
| 47 | -3602 |
| 48 | 4063 |
| 49 | -4560 |
| 50 | 5092 |
| 51 | -5704 |
| 52 | 6400 |
| 53 | -7150 |
| 54 | 7966 |