Representing Graphs as the Intersection of Cographs and Threshold Graphs
نویسندگان
چکیده
A graph $G$ is said to be the intersection of graphs $G_1,G_2,\ldots,G_k$ if $V(G)=V(G_1)=V(G_2)=\cdots=V(G_k)$ and $E(G)=E(G_1)\cap E(G_2)\cap\cdots\cap E(G_k)$. For a $G$, $\dim_{COG}(G)$ (resp. $\dim_{TH}(G)$) denotes minimum number cographs threshold graphs) whose gives $G$. We present several new bounds on these parameters for general as well some special classes graphs. It shown that any $G$: (a) $\dim_{COG}(G)\leqslant\mathrm{tw}(G)+2$, (b) $\dim_{TH}(G)\leqslant\mathrm{pw}(G)+1$, (c) $\dim_{TH}(G)\leqslant\chi(G)\cdot\mathrm{box}(G)$, where $\mathrm{tw}(G)$, $\mathrm{pw}(G)$, $\chi(G)$ $\mathrm{box}(G)$ denote respectively treewidth, pathwidth, chromatic boxicity also derive exact values cycles show every forest two cographs. These results allow us improved $\dim_{TH}(G)$ when belongs classes.
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ژورنال
عنوان ژورنال: Electronic Journal of Combinatorics
سال: 2021
ISSN: ['1077-8926', '1097-1440']
DOI: https://doi.org/10.37236/9110