Integral Cayley graphs over dihedral groups
نویسندگان
چکیده
منابع مشابه
Integral Cayley Graphs over Abelian Groups
Let Γ be a finite, additive group, S ⊆ Γ, 0 6∈ S, − S = {−s : s ∈ S} = S. The undirected Cayley graph Cay(Γ, S) has vertex set Γ and edge set {{a, b} : a, b ∈ Γ, a − b ∈ S}. A graph is called integral, if all of its eigenvalues are integers. For an abelian group Γ we show that Cay(Γ, S) is integral, if S belongs to the Boolean algebra B(Γ) generated by the subgroups of Γ. The converse is proven...
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ژورنال
عنوان ژورنال: Journal of Algebraic Combinatorics
سال: 2017
ISSN: 0925-9899,1572-9192
DOI: 10.1007/s10801-017-0787-x