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تسجيل مستخدم جديدFurther Inequalities Between Vertex-Degree-Based Topological Indices
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Continuing the recent work of L. Zhong and K. Xu [MATCH Commun. Math. Comput. Chem.71(2014) 627-642], we determine inequalities among several vertex-degree-based topological indices; first geometric-arithmetic index(GA), augmented Zagreb index (AZI), Randi$acute{c}$ index (R), atom-bond connectivity index (ABC), sum-connectivity index (X)and harmonic index (H).
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Let $D=(V,A)$ be a digraphs without isolated vertices. A vertex-degree based invariant $I(D)$ related to a real function $varphi$ of $D$ is defined as a summation over all arcs, $I(D) = frac{1}{2}sum_{uvin A}{varphi(d_u^+,d_v^-)}$, where $d_u^+$ (res
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