The total irregularity of a graph July 24 , 2012
نویسندگان
چکیده
In this note a new measure of irregularity of a simple undirected graph G is introduced. It is named the total irregularity of a graph and is defined as irrt(G) = 1 2 ∑ u,v∈V (G) |dG(u)− dG(v)| , where dG(u) denotes the degree of a vertex u ∈ V (G). The graphs with maximal total irregularity are determined. It is also shown that among all trees of same order the star graph has the maximal total irregularity.
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