The perfect matching index of a cubic graph , denoted by , is the smallest number of perfect matchings that cover all the edges of . According to the Berge-Fulkerson conjecture, for every bridgeless cubic graph~. The class of graphs with is of particular interest as many conjectures and open problems, including the famous cycle double cover conjecture, can be reduced to it. Although nontrivial examples of such graphs are very difficult to find, a few infinite families are known, all with circular flow number . It has been therefore suggested [Electron. J. Combin. 23 (2016), P3.54] that might imply $\Phi_c(G)\ge 545\pi\ge 5\Phi_c\le 4+\frac23$.

生成讲解博客的中文版本

生成AI智能校验的中文版本