Graphs with prescribed star complement for the eigenvalue 1
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چکیده
Let G be a graph of order n and let μ be an eigenvalue of multiplicity m. A star complement for μ in G is an induced subgraph of G of order n−m with no eigenvalue μ. In this paper, we study the maximal graphs as well as regular graphs which have Kr,s + tK1 as a star complement for eigenvalue 1. It turns out that some well known strongly regular graphs are uniquely determined by such a star complement. AMS Subject Classification: 05C50.
منابع مشابه
Graphs with prescribed star complement for 1 as the second largest eigenvalue
Let G be a graph of order n and let μ be an eigenvalue of multiplicity m. A star complement for μ in G is an induced subgraph of G of order n −m with no eigenvalue μ. In this paper, we study maximal and regular graphs which have Kr,s + tK1 as a star complement for 1 as the second largest eigenvalue. It turns out that some well known strongly regular graphs are uniquely determined by such a star...
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تاریخ انتشار 2008