Principal Common Divisors of Graphs
نویسندگان
چکیده
منابع مشابه
Integral Cayley Graphs Defined by Greatest Common Divisors
An undirected graph is called integral, if all of its eigenvalues are integers. Let Γ = Zm1 ⊗· · ·⊗Zmr be an abelian group represented as the direct product of cyclic groups Zmi of order mi such that all greatest common divisors gcd(mi,mj) ≤ 2 for i 6= j. We prove that a Cayley graph Cay(Γ, S) over Γ is integral, if and only if S ⊆ Γ belongs to the the Boolean algebra B(Γ) generated by the subg...
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ژورنال
عنوان ژورنال: European Journal of Combinatorics
سال: 1993
ISSN: 0195-6698
DOI: 10.1006/eujc.1993.1012