Line graphs with exactly two positive eigenvalues
نویسندگان
چکیده
منابع مشابه
Small graphs with exactly two non-negative eigenvalues
Let $G$ be a graph with eigenvalues $lambda_1(G)geqcdotsgeqlambda_n(G)$. In this paper we find all simple graphs $G$ such that $G$ has at most twelve vertices and $G$ has exactly two non-negative eigenvalues. In other words we find all graphs $G$ on $n$ vertices such that $nleq12$ and $lambda_1(G)geq0$, $lambda_2(G)geq0$ and $lambda_3(G)0$, $lambda_2(G)>0$ and $lambda_3(G)
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ژورنال
عنوان ژورنال: Publications de l'Institut Mathematique
سال: 2002
ISSN: 0350-1302
DOI: 10.2298/pim0272039b