Some results on graphs with exactly two main eigenvalues
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چکیده
منابع مشابه
Some results on graphs with exactly two main eigenvalues
where ni = nβ 2 i (i = 1, 2); β1 and β2 denote the main angles of μ1 and μ2, respectively. Further, let G be any connected or disconnected graph (not necessarily with two main eigenvalues). Let S be any subset of the vertex set V (G) and let GS be the graph obtained from the graph G by adding a new vertex x which is adjacent exactly to the vertices from S. If σ(GS1) = σ(GS2) then we prove that ...
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ژورنال
عنوان ژورنال: Applied Mathematics Letters
سال: 2012
ISSN: 0893-9659
DOI: 10.1016/j.aml.2011.11.025