Multiplicities of Eigenvalues and Tree-Width of Graphs
نویسندگان
چکیده
منابع مشابه
Multiplicities of Eigenvalues and Tree-Width of Graphs
Definition 1. OG is the set of real symmetric V_V matrices with entries ai, j such that ai, j<0 if [i, j] # E and ai, j=0 if i{ j and [i, j] E. An operator A # OG has a non-degenerate first eigenvalue *1 (groundstate) if G is connected (Perron and Frobenius). The invariant +(G) is defined using multiplicities of the second eigenvalue *2 for some real symmetric matrix A # OG . Moreover, +(G) is ...
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ژورنال
عنوان ژورنال: Journal of Combinatorial Theory, Series B
سال: 1998
ISSN: 0095-8956
DOI: 10.1006/jctb.1998.1834