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 | -11 |
| 10 | 7 |
| 11 | 3 |
| 12 | 15 |
| 13 | 35 |
| 14 | 71 |
| 15 | -35 |
| 16 | 25 |
| 17 | -57 |
| 18 | -99 |
| 19 | -277 |
| 20 | -415 |
| 21 | 25 |
| 22 | -185 |
| 23 | 39 |
| 24 | 327 |
| 25 | 1079 |
| 26 | 1895 |
| 27 | 3745 |
| 28 | -71 |
| 29 | 2907 |
| 30 | 813 |
| 31 | 479 |
| 32 | -4927 |
| 33 | -7259 |
| 34 | -20393 |
| 35 | -29877 |
| 36 | -8409 |
| 37 | -28621 |
| 38 | -23041 |
| 39 | -16811 |
| 40 | 4441 |
| 41 | 27783 |
| 42 | 102741 |
| 43 | 169595 |
| 44 | 324065 |
| 45 | 105265 |
| 46 | 361471 |
| 47 | 280983 |
| 48 | 385215 |