On Integral Complete R−partite Graphs
نویسنده
چکیده
A graph G is called integral if all the eigenvalues of its adjacency matrix are integers. In this paper we investigate integral complete r−partite graphs Kp1,p2,...,pr = Ka1p1,a2p2,...,asps with s ≤ 4. New sufficient conditions for complete 3-partite graphs and complete 4-partite graphs to be integral are given. From these conditions we construct infinitely many new classes of integral complete r−partite graphs for s = 3, 4. Moreover, the summary of our results about integral complete 3-partite graphs and integral complete 4-partite graphs can be found in the paper. Mathematics Subject Classification 2000: 05C75 Additional
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تاریخ انتشار 2010