On the Sum and Product of Covering Numbers of Graphs and their Line Graphs

Susanth C ., Sunny Joseph Kalayathankal


The bounds on the sum and product of chromatic numbers of a graph and its complement are known as Nordhaus-Gaddum inequalities. In this paper, we study the bounds on the sum and product of the covering numbers of graphs and their line graphs. We also provide a new characterization of the certain graph classes.


Covering number; Independence number; Matching number; Line graph

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DOI: http://dx.doi.org/10.26713%2Fcma.v6i1.275


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