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Cullen numbers with the Lehmer property

Authors: José María Grau Ribas and Florian Luca
Journal: Proc. Amer. Math. Soc. 140 (2012), 129-134
MSC (2010): Primary 11A05; Secondary 11N25, 11A07
Published electronically: May 20, 2011
Corrigendum: Proc. Amer. Math. Soc. 141 (2013), 2941-2943
MathSciNet review: 2833524
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Abstract | References | Similar Articles | Additional Information

Abstract: Here, we show that there is no positive integer $ n$ such that the $ n$th Cullen number $ C_n=n2^n+1$ has the property that it is composite but $ \phi(C_n)\mid C_n-1$.

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Additional Information

José María Grau Ribas
Affiliation: Departamento de Mátematicas, Universidad de Oviedo, Avenida Calvo Sotelo, s/n, 33007 Oviedo, Spain

Florian Luca
Affiliation: Instituto de Matemáticas, Universidad Nacional Autonoma de México, C.P. 58089, Morelia, Michoacán, México

Received by editor(s): October 14, 2010
Received by editor(s) in revised form: November 11, 2010
Published electronically: May 20, 2011
Communicated by: Matthew A. Papanikolas
Article copyright: © Copyright 2011 American Mathematical Society