The harmonic index of two-trees and quasi-tree graphs
نویسندگان
چکیده
منابع مشابه
On the harmonic index of bicyclic graphs
The harmonic index of a graph $G$, denoted by $H(G)$, is defined asthe sum of weights $2/[d(u)+d(v)]$ over all edges $uv$ of $G$, where$d(u)$ denotes the degree of a vertex $u$. Hu and Zhou [Y. Hu and X. Zhou, WSEAS Trans. Math. {bf 12} (2013) 716--726] proved that for any bicyclic graph $G$ of order $ngeq 4$, $H(G)le frac{n}{2}-frac{1}{15}$ and characterize all extremal bicyclic graphs.In this...
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ژورنال
عنوان ژورنال: Journal of Mathematical Inequalities
سال: 2019
ISSN: 1846-579X
DOI: 10.7153/jmi-2019-13-32