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harmonic-arithmetic index of unicyclic graphs
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نویسنده
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ding guoqing ,zhong lingping ,wang xia
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منبع
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iranian journal of mathematical chemistry - 2025 - دوره : 16 - شماره : 2 - صفحه:93 -108
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چکیده
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let g=(v(g),e(g)) be a graph. the harmonic-arithmetic index of g is defined as ha(g)=sum_{uvin e(g)}frac{4d_{g}(u)d_{g}(v)}{(d_{g}(u)+d_{g}(v))^2}, where d_{g}(u) is the degree of a vertex uin v(g). in this paper, we consider the upper and lower bounds of the harmonic-arithmetic index of unicyclic graphs with a fixed order. furthermore, the graphs attaining the extremal values are also characterised.
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کلیدواژه
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harmonic-arithmetic index ,extremal graph ,unicyclic graph
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آدرس
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nanjing university of aeronautics and astronautics, school of mathematics, china, nanjing university of aeronautics and astronautics, school of mathematics, china, nanjing university of aeronautics and astronautics, school of mathematics, china
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پست الکترونیکی
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wx20010704zlnl@163.com
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Authors
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