More on Zagreb Coindices of Composite Graphs

نویسندگان

  • Maolin Wang
  • Hongbo Hua
چکیده

For a nontrivial graph G, its first and second Zagreb coindices are defined [1], respectively, as M1(G) = ∑ uv ∈E(G) (dG(u)+dG(v)) and M2(G) = ∑ uv ∈E(G) dG(u)dG(v), where dG(x) is the degree of vertex x in G. In this paper, we obtained some new properties of Zagreb coindices. We mainly give explicit formulae for the first Zagreb coindex of line graphs and total graphs. Mathematics Subject Classification: 05C90; 05C35 05C12

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تاریخ انتشار 2011