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arXiv · 1201.0798

Circulant Digraphs Integral over Number Fields

Fei Li
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Abstract

A number field K is a finite extension of rational number field Q. A circulant digraph integral over K means that all its eigenvalues are algebraic integers of K. In this paper we give the sufficient and necessary condition for circulant digraphs which are integral over a number field K. And we solve the Conjecture3.3 in [XM] and find it is affirmative.

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Fei Li. 2012-01-04. Circulant Digraphs Integral over Number Fields. https://doi.org/10.1016/j.disc.2012.12.025

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