On Variable Sum Exdeg Indices of Quasi-Tree Graphs and Unicyclic Graphs
نویسندگان
چکیده
منابع مشابه
On the variable sum exdeg index and cut edges of graphs
The variable sum exdeg index of a graph G is defined as $SEI_a(G)=sum_{uin V(G)}d_G(u)a^{d_G(u)}$, where $aneq 1$ is a positive real number, du(u) is the degree of a vertex u ∈ V (G). In this paper, we characterize the graphs with the extremum variable sum exdeg index among all the graphs having a fixed number of vertices and cut edges, for every a>1.
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A connected graph G = (V, E) is called a quasi-tree graph if there exists a vertex u0 ∈ V (G) such that G−u0 is a tree. A connected graph G = (V, E) is called a quasi-unicyclic graph if there exists a vertex u0 ∈ V (G) such that G− u0 is a unicyclic graph. Set T (n, k) := {G : G is a n-vertex quasi-tree graph with k pendant vertices}, and T (n, d0, k) := {G : G ∈ T (n, k) and there is a vertex ...
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ژورنال
عنوان ژورنال: Discrete Dynamics in Nature and Society
سال: 2020
ISSN: 1026-0226,1607-887X
DOI: 10.1155/2020/1317295