Recently the exponential Randić index $ {{\rm e}^{\chi}} $ was introduced. The exponential Randić index of a graph $ G $ is defined as the sum of the weights $ {{\rm e}^{{\frac {1}{\sqrt {d \left(u \right) d \left(v \right) }}}}} $ of all edges $ uv $ of $ G $, where $ d(u) $ denotes the degree of a vertex $ u $ in $ G $. In this paper, we give sharp lower and upper bounds on the exponential Randić index of unicyclic graphs.
Citation: Qian Lin, Yan Zhu. Unicyclic graphs with extremal exponential Randić index[J]. Mathematical Modelling and Control, 2021, 1(3): 164-171. doi: 10.3934/mmc.2021015
Recently the exponential Randić index $ {{\rm e}^{\chi}} $ was introduced. The exponential Randić index of a graph $ G $ is defined as the sum of the weights $ {{\rm e}^{{\frac {1}{\sqrt {d \left(u \right) d \left(v \right) }}}}} $ of all edges $ uv $ of $ G $, where $ d(u) $ denotes the degree of a vertex $ u $ in $ G $. In this paper, we give sharp lower and upper bounds on the exponential Randić index of unicyclic graphs.
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Qian Lin, Yan Zhu. Unicyclic graphs with extremal exponential Randić index[J]. Mathematical Modelling and Control, 2021, 1(3): 164-171. doi: 10.3934/mmc.2021015
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