Some families of integral graphs
نویسندگان
چکیده
منابع مشابه
Some families of integral graphs
A graph is called integral if all its eigenvalues (of the adjacency matrix) are integers. In this paper, the graphs K1,r •Kn , r ∗Kn , K1,r • Km,n , r ∗ Km,n and the tree K1,s • T (q, r,m, t) are defined. We determine the characteristic polynomials of these graphs and also obtain sufficient and necessary conditions for these graphs to be integral. Some sufficient conditions are found by using t...
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ژورنال
عنوان ژورنال: Discrete Mathematics
سال: 2008
ISSN: 0012-365X
DOI: 10.1016/j.disc.2007.12.010