Q-spectral characterization of multicones over some regular graphs
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摘要: 研究了锥图G Ks的 Q- 谱确定性, 其中 G 为 n 阶 r－正则图,Ks 为 s 阶完全图. 证明了, 对于任意正整数 s, 当 r=n-2 (n 4)时,G Ks 由其 Q- 谱确定; 当r=n-3 (n 6)时,G Ks 由其Q- 谱确定当且仅当 G 的补图 overline{G} 不含 三角形 C3.Abstract: The Q-spectral characterization of the multicone graphG Ks is investigated, where G is a r-regular graph of order n and Ks is a complete graph of order s. We prove that for any positive integer s, the multicone graphG Ks is determined by its Q-spectrum if r = n2 and n 4. We also show that for any positive integer s, if r = n3 and n 6, the multicone graphG Ks is determined by its Q-spectrum if and only if the complement of G has no triangles.
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