Isnaini Rosyida, Widodo, Ch. R. Indrati, K.A. Sugeng
Upper bounds for sum and product of chromatic number of complementary fuzzy graphs are given in [9]. We find that these bounds do not hold for fuzzy graphs which have certain properties. This problem motivates us to investigate upper bounds for sum and product of chromatic number of several classes of fuzzy graphs and their complements. We obtain new results on upper bounds for sum and product of complementary fuzzy graphs. Finally, we investigate these results related to the bounds given in [9]. We add a necessary condition to fuzzy graphs so that the upper bounds given in [9] can be improved. © 2014 Pushpa Publishing House, Allahabad, India.
Department of Mathematics, GadjahMada University, Indonesia; Department of Mathematics, Semarang State University, Indonesia; Department of Mathematics, University of Indonesia, Indonesia
