The Second and Third Geometric-Arithmetic Indices of Unicyclic Graphs

The Second and Third Geometric-Arithmetic Indices of Unicyclic Graphs

Recently, G. Fath-Tabar, B. Furtula and I. Gutman (A new geometricarithmetic index, J. Math. Chem. 47, 477–486, 2010) proposed the second geometric-arithmetic index GA2 and B. Zhou, I. Gutman, B. Furtula and Z. Du (On two types of geometric-arithmetic index, Chem. Phys. Lett. 482, 153–155, 2009) put forward the third geometricarithmetic index GA3, respectively. In (Gutman, I. and Furtula, B. Estimating the second and third geometric-arithmetic indices, Hacet. J. Math. Stat. 40 (1), 69–76, 2011), inequalities between GA2 and GA3 for trees, with the number of vertices and the number of pendent vertices, were obtained by I. Gutman and B. Furtula. In this paper, we obtain inequalities between the two indices for unicyclic graphs.

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  • Fath-Tabar, G., Furtula, B. and Gutman, I. A new geometric-arithmetic index, J. Math. Chem. 47, 477–486, 2010.
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  • Gutman, I. and Furtula, B. Estimating the second and third geometric-arithmetic indices, Hacet. J. Math. Stat. 40 (1), 69–76, 2011.
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  • Zhou, B., Gutman, I., Furtula, B. and Du, Z. On two types of geometric-arithmetic index, Chem. Phys. Lett. 482, 153–155, 2009.