Abstract
Let G be a connected graph with order n, minimum degree δ = δ(G) and edge-connectivity λ = λ(G). A graph G is maximally edge-connected if λ = δ, and super edge-connected if every minimum edgecut consists of edges incident with a vertex of minimum degree. Define the zeroth-order general Randić index \(R_\alpha ^0\left( G \right) = \sum\limits_{x \in V\left( G \right)} {d_G^\alpha \left( x \right)} \) , where dG(x) denotes the degree of the vertex x. In this paper, we present two sufficient conditions for graphs and triangle-free graphs to be super edge-connected in terms of the zeroth-order general Randić index for −1 ≤ α < 0, respectively.
Similar content being viewed by others
References
Bauer, D., Boesch, F.T., Suffel, C., Tindell, R. Connectivity extremal problems and the design of reliable probabilistic networks. In: the Theory and Application of Graphs, G. Chartrand, Y. Alavi, D. Goldsmith, L. Lesniak Foster, and D. Lick, eds. Wiley, New York, 1981, 45–54
Boesch, F. On unreliability polynomials and graph connectivity in reliable network synthesis. J. Graph Theory, 10: 339–352 (1986)
Bondy, J.A., Murty, U.S.R. Graph Theory with Application. Elsevier, New York, 1976
Chartrand, G. A graph-theoretic approach to a communications problem. SIAM J. Appl. Math., 14: 778–781 (1966)
Chen, Z., Su, G., Volkmann, L. Sufficient conditions on the zeroth-order general Randić index for maximally edge-connected graphs. Discrete Appl. Math., 218: 64–70 (2017)
Dankelmann, P., Hellwig, A., Volkmann, L. Inverse degree and edge-connectivity. Discrete Math., 309: 2943–2947 (2009)
Dankelmann, P., Volkmann, L. New sufficient conditions for equality of minimum degree and edgeconnectivity. Ars Combin., 40: 270–278 (1995)
Dankelmann, P., Volkmann, L. Degree sequence condition for maximally edge-connected graphs depending on the clique number. Discrete Math., 211: 217–223 (2000)
Dankelmann, P., Volkmann, L. Degree sequence condition for maximally edge-connected graphs and digraphs. J. Graph Theory, 26: 27–34 (1997)
Fiol, M.A. On super-edge-connected digraphs and bipartite digraphs. J. Graph Theory, 16: 545–555 (1992)
Kelmans, A.K. Asymptotic formulas for the probability of k-connectedness of random graphs. Theory Probab. Appl., 17: 243–254 (1972)
Lesniak, L. Results on the edge-connectivity of graphs. Discrete Math., 8: 351–354 (1974)
Lin, A., Luo, R., Zha, X. On sharp bounds of the zeroth-order general Randić index of certain unicyclic graphs. Appl. Math. Lett., 22: 585–589 (2009)
Li, X., Zheng, J. A unified approach to the extremal trees for different indices. MATCH Commun Math. Comput. Chem., 51: 195–208 (2005)
Plesník, L., Znám, S. On equality of edge-connectivity and minimum degree of a graph. Arch. Math. (Brno), 25: 19–25 (1989)
Soneoka, T. Super-edge-connectivity of dense digraphs and graphs. Discrete Appl. Math., 37/38: 511–523 (1992)
Su, G., Xiong, L., Su, X., Li, G. Maximally edge-connected graphs and zeroth-order general Randić index for a = -1. J. Comb. Optim., 31: 182–195 (2016)
Tian, Y., Guo, L., Meng, J., Qin, C. Inverse degree and super dege-connectivity. Int. J. Comput. Math., 89(6): 752–759 (2012)
Turán, P. Eine Extremalaufgabe aus der Graphentheorie. Mat. Fiz. Lapook, 48: 436–452 (1941)
Acknowledgements
The authors wish to thank the referee for useful comments and suggestions that have allowed them to improve the presentation of the paper.
Author information
Authors and Affiliations
Corresponding author
Additional information
This work is supported by the National Natural Science Foundation of China (No.11501490, 61373019, 11371307) and by the Natural Science Foundation of Shandong Province (No. ZR2015AM006).
Rights and permissions
About this article
Cite this article
He, Zh., Lu, M. Super Edge-connectivity and Zeroth-order General Randić Index for −1 ≤ α < 0. Acta Math. Appl. Sin. Engl. Ser. 34, 659–668 (2018). https://doi.org/10.1007/s10255-018-0775-5
Received:
Revised:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s10255-018-0775-5