2-Connected graphs with minimum general sum-connectivity index
نویسندگان
چکیده
منابع مشابه
2-Connected graphs with minimum general sum-connectivity index
The general sum-connectivity index of a graph G is χα(G) = ∑ uv∈E(G) (d(u)+d(v)), where d(u) denotes the degree of vertex u ∈ V (G), and α is a real number. In this paper, we show that in the class of graphs G of order n ≥ 3 and minimum degree δ(G) ≥ 2, the unique graph G having minimum χα(G) is K2 + Kn−2 if −1 ≤ α < α0 ≈ −0.867. Similarly, if we impose the supplementary condition for G to be t...
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Let $G=(V,E)$ be a simple connectedgraph with $n$ vertices, $m$ edges and sequence of vertex degrees$d_1 ge d_2 ge cdots ge d_n>0$, $d_i=d(v_i)$, where $v_iin V$. With $isim j$ we denote adjacency ofvertices $v_i$ and $v_j$. The generalsum--connectivity index of graph is defined as $chi_{alpha}(G)=sum_{isim j}(d_i+d_j)^{alpha}$, where $alpha$ is an arbitrary real<b...
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ژورنال
عنوان ژورنال: Discrete Applied Mathematics
سال: 2014
ISSN: 0166-218X
DOI: 10.1016/j.dam.2014.06.023