The Nordhaus-Gaddum-type inequalities for the Zagreb index and co-index of graphs

Abstract Let k ≥ 2 be an integer, a k -decomposition ( G 1 , G 2 , … , G k ) of the complete graph K n is a partition of its edge set to form k spanning subgraphs G 1 , G 2 , … , G k . In this contribution, we investigate the Nordhaus–Gaddum-type inequality of a k -decomposition of K n for the general Zagreb index and a 2 -decomposition for the Zagreb co-indices, respectively. The corresponding extremal graphs are characterized.

[1]  Shaoji Xu Some parameters of graph and its complement , 1987, Discret. Math..

[2]  Ali Reza Ashrafi,et al.  The first and second Zagreb indices of some graph operations , 2009, Discret. Appl. Math..

[3]  Yun Wang,et al.  Nordhaus-Gaddum-Type Theorem for Diameter of Graphs when Decomposing into Many Parts , 2011, Discret. Math. Algorithms Appl..

[4]  ˇ TomislavDo,et al.  Vertex-Weighted Wiener Polynomials for Composite Graphs , 2008 .

[5]  J. A. Bondy,et al.  Graph Theory with Applications , 1978 .

[6]  Ali Reza Ashrafi,et al.  The Zagreb coindices of graph operations , 2010, Discret. Appl. Math..

[7]  Sonja Nikolic,et al.  The Vertex-Connectivity Index Revisited , 1998, J. Chem. Inf. Comput. Sci..

[8]  I. W Nowell,et al.  Molecular Connectivity in Structure-Activity Analysis , 1986 .

[9]  Pierre Hansen,et al.  Graphs with maximum connectivity index , 2003, Comput. Biol. Chem..

[10]  R. Jackson Inequalities , 2007, Algebra for Parents.

[11]  Ali Reza Ashrafi,et al.  Extremal Graphs with Respect to the Zagreb Coindices , 2011 .

[12]  Ernst Hairer,et al.  Analysis by Its History , 1996 .

[13]  N. Trinajstic,et al.  The Zagreb Indices 30 Years After , 2003 .

[14]  Béla Bollobás,et al.  Graphs of Extremal Weights , 1998, Ars Comb..

[15]  Roberto Todeschini,et al.  Handbook of Molecular Descriptors , 2002 .

[16]  E. A. Nordhaus,et al.  On Complementary Graphs , 1956 .

[17]  I. Gutman,et al.  Graph theory and molecular orbitals. Total φ-electron energy of alternant hydrocarbons , 1972 .