Integral equienergetic non-isospectral unitary Cayley graphs
نویسندگان
چکیده
We prove that the Cayley graphs $X(G,S)$ and $X^+(G,S)$ are equienergetic for any abelian group $G$ symmetric subset $S$. then focus on family of unitary $G_R=X(R,R^*)$, where $R$ is a finite commutative ring with identity. show under mild conditions, $\{G_R, G_R^+\}$ pairs integral non-isospectral (generically connected non-bipartite). Then, we obtain conditions such \bar G_R\}$ graphs. Finally, characterize all triples G_R^+, G_R \}$ also Ramanujan.
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ژورنال
عنوان ژورنال: Linear Algebra and its Applications
سال: 2021
ISSN: ['1873-1856', '0024-3795']
DOI: https://doi.org/10.1016/j.laa.2020.12.001