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Register a new userThe enhanced quotient graph of the quotient of a finite group
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For a finite group $G$ with a normal subgroup $H$, the enhanced quotient graph of $G/H$, denoted by $mathcal{G}_{H}(G),$ is the graph with vertex set $V=(Gbackslash H)cup {e}$ and two vertices $x$ and $y$ are edge connected if $xH = yH$ or $xH,yHin langle zHrangle$ for some $zin G$. In this article, we characterize the enhanced quotient graph of $G/H$. The graph $mathcal{G}_{H}(G)$ is complete if and only if $G/H$ is cyclic, and $mathcal{G}_{H}(G)$ is Eulerian if and only if $|G/H|$ is odd. We show some relation between the graph $mathcal{G}_{H}(G)$ and the enhanced power graph $mathcal{G}(G/H)$ that was introduced by Sudip Bera and A.K. Bhuniya (2016). The graph $mathcal{G}_H(G)$ is complete if and only if $G/H$ is cyclic if and only if $mathcal{G}(G/H)$ is complete. The graph $mathcal{G}_H(G)$ is Eulerian if and only if $|G|$ is odd if and only if $mathcal{G}(G)$ is Eulerian, i.e., the property of being Eulerian does not depend on the normal subgroup $H$.
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