Eigenvalues and expansion of bipartite graphs
نویسندگان
چکیده
منابع مشابه
Eigenvalues and expansion of bipartite graphs
We prove lower bounds on the largest and second largest eigenvalue of the adjacency matrix of connected bipartite graphs and give necessary and sufficient conditions for equality. We give several examples of classes of graphs that are optimal with respect to the bounds. We prove that BIBD-graphs are characterized by their eigenvalues. Finally we present a new bound on the expansion coefficient ...
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ژورنال
عنوان ژورنال: Designs, Codes and Cryptography
سال: 2012
ISSN: 0925-1022,1573-7586
DOI: 10.1007/s10623-011-9598-6