On Comparing Variable Zagreb Indices for Unicyclic Graphs
نویسندگان
چکیده
Recently, the first and second Zagreb indices are generalized into the variable Zagreb indices which are defined by M1(G) = ∑ u∈V (d(u))2λ and M2(G) = ∑ uv∈E (d(u)d(v)), where λ is any real number. In this paper, we prove that M1(G)/n M2(G)/m for all unicyclic graphs and all λ ∈ (−∞, 0]. And we also show that the relationship of numerical value between M1(G)/n and M2(G)/m is indefinite in the distinct unicyclic graphs for each λ ∈ (1,+∞). With the conclusion in [4], we finish discussing the relationship of M1(G)/n and M2(G)/m in unicyclic graphs for λ ∈ R.
منابع مشابه
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