Some New Bounds for a Real Power of the Normalized Laplacian Eigenvalues
نویسنده
چکیده
the reader to [1], [16], [17], [21], and their bibliographies, to get a taste of the variety of approaches used to study this descriptor. In [28], Zhou et al. studied the extremal graphs with given matching number, connectivity and the minimal Kirchhoff index. Also in [23], [25] and [26] the authors determined independently the extremality on the unicyclic graphs with respect to the Kirchhoff index. Moreover, in [27], Zhou et al. presented some lower bounds for the Kirchhoff index of a connected (molecular) graph via the number of vertices (atoms), the number of edges (bands), valency (maximum vertex degree), connectivity and chromatic number. The degree Kirchhoff index was proposed by Chen and Zhang in [7], defined as
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