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 | -2 |
| 4 | 4 |
| 5 | -5 |
| 6 | 9 |
| 7 | -15 |
| 8 | 23 |
| 9 | -38 |
| 10 | 62 |
| 11 | -99 |
| 12 | 161 |
| 13 | -261 |
| 14 | 421 |
| 15 | -682 |
| 16 | 1104 |
| 17 | -1785 |
| 18 | 2889 |
| 19 | -4675 |
| 20 | 7563 |
| 21 | -12238 |
| 22 | 19802 |
| 23 | -32039 |
| 24 | 51841 |
| 25 | -83881 |
| 26 | 135721 |
| 27 | -219602 |
| 28 | 355324 |
| 29 | -574925 |
| 30 | 930249 |
| 31 | -1505175 |
| 32 | 2435423 |
| 33 | -3940598 |
| 34 | 6376022 |
| 35 | -10316619 |
| 36 | 16692641 |
| 37 | -27009261 |
| 38 | 43701901 |
| 39 | -70711162 |
| 40 | 114413064 |
| 41 | -185124225 |