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arXiv · 2205.09955

Maximum zeroth-order general Randi\'{c} index of orientations of cacti

Jiaxiang Yang·Hanyuan Deng·Zikai Tang·Hechao Liu
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Abstract

The zeroth-order general Randi\'{c} index $R^{0}_{a+1}$ of an $n$-vertices oriented graph $D$ is equal to the sum of $(d^{+}_{u_i})^{a}+(d^{-}_{u_j})^{a}$ over all arcs $u_iu_j$ of $D$, where we denote by $d^{+}_{u_i}$ the out-degree of the vertex $u_i$ and $d^{-}_{u_j}$ the in-degree of the vertex $u_j$, $a$ is an arbitrary real number. In the paper, we determine the orientations of cacti with the maximum value of the zeroth-order general Randi\'{c} index for $a\geq 1$.

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Jiaxiang Yang, Hanyuan Deng, Zikai Tang, Hechao Liu. 2022-05-20. Maximum zeroth-order general Randi\'{c} index of orientations of cacti. https://arxiv.org/abs/2205.09955

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