%0 Journal Article %T Extended results on two domination number and chromatic number of a graph %A G. Mahadevan %A A. Selvam avadyappan %A A. Mydeen bibi %J International Journal of Mathematics and Soft Computing %D 2011 %I SweDha Publication %X A subset S of V is called a dominating set in G if every vertex in V-S is adjacent to at least one vertex in S. A Dominating set is said to be two dominating set if every vertex in V-S is adjacent to atleast two vertices in S. The minimum cardinality taken over all, the minimal two dominating set is called two domination number and is denoted by ¦Ã2 (G). The minimum number of colors required to colour all the vertices such that adjacent vertices do not receive the same colour is the chromatic number ¦Ö (G). In [6], it was proved that sum of two domination number and chromatic number is equals to 2n-5 and 2n-6. In this paper, we characterize all graphs whose sum of two domination number and chromatic number is 2n-7. %K Two Domination Number %K Chromatic Number %U http://ijmsc.com/index.php/ijmsc/article/view/34/pdf