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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 $H$.
Given two $n_i$-dimensional Alexandrov spaces $X_i$ of curvature $ge 1$, the join of $X_1$ and $X_2$ is an $(n_1+n_2+1)$-dimensional Alexandrov space $X$ of curvature $ge 1$, which contains $X_i$ as convex subsets such that their points are $frac pi2
A group $G$ is said to be $frac{3}{2}$-generated if every nontrivial element belongs to a generating pair. It is easy to see that if $G$ has this property then every proper quotient of $G$ is cyclic. In this paper we prove that the converse is true f
We classify all $n$-dimensional reduced Cohen-Macaulay modular quotient variety $mathbb{A}_mathbb{F}^n/C_{2p}$ and study their singularities, where $p$ is a prime number and $C_{2p}$ denotes the cyclic group of order $2p$. In particular, we present a
For a group $G$, we define a graph $Delta(G)$ by letting $G^{#} = G setminus { 1 }$ be the set of vertices and by drawing an edge between distinct elements $x,yin G^{#}$ if and only if the subgroup $langle x,yrangle$ is cyclic. Recall that a $Z$-grou
We find a relation between the genus of a quotient of a numerical semigroup $S$ and the genus of $S$ itself. We use this identity to compute the genus of a quotient of $S$ when $S$ has embedding dimension $2$. We also exhibit identities relating the