Maximum first Zagreb index of orientations of unicyclic graphs with given matching number

نویسندگان

چکیده

Let D=(V,A) be a digraphs without isolated vertices. The first Zagreb index of digraph D is defined as summation over all arcs, M1(D)=12∑uv∈A(du++dv−), where du+(resp. du−) denotes the out-degree (resp. in-degree) vertex u. In this paper, we give maximal values and set orientations unicyclic graphs with n vertices matching number m (2≤m≤⌊n2⌋).

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ژورنال

عنوان ژورنال: Applied Mathematics and Computation

سال: 2022

ISSN: ['1873-5649', '0096-3003']

DOI: https://doi.org/10.1016/j.amc.2022.127131