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 | 5 |
| 6 | -5 |
| 7 | 8 |
| 8 | -7 |
| 9 | 13 |
| 10 | -13 |
| 11 | 18 |
| 12 | -19 |
| 13 | 26 |
| 14 | -29 |
| 15 | 39 |
| 16 | -40 |
| 17 | 52 |
| 18 | -60 |
| 19 | 72 |
| 20 | -81 |
| 21 | 101 |
| 22 | -113 |
| 23 | 134 |
| 24 | -152 |
| 25 | 181 |
| 26 | -206 |
| 27 | 243 |
| 28 | -273 |
| 29 | 318 |
| 30 | -365 |
| 31 | 418 |
| 32 | -473 |
| 33 | 549 |
| 34 | -620 |
| 35 | 710 |
| 36 | -803 |
| 37 | 914 |
| 38 | -1034 |
| 39 | 1177 |
| 40 | -1322 |
| 41 | 1498 |
| 42 | -1691 |
| 43 | 1904 |
| 44 | -2139 |
| 45 | 2416 |
| 46 | -2704 |
| 47 | 3036 |
| 48 | -3400 |
| 49 | 3811 |
| 50 | -4261 |