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Factors of generalized Fermat numbers


Authors: Harvey Dubner and Wilfrid Keller
Journal: Math. Comp. 64 (1995), 397-405
MSC: Primary 11A51; Secondary 11Y05
DOI: https://doi.org/10.1090/S0025-5718-1995-1270618-1
MathSciNet review: 1270618
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Abstract: Generalized Fermat numbers have the form $ {F_{b,m}} = {b^{{2^m}}} + 1$. Their odd prime factors are of the form $ k \cdot {2^n} + 1$, k odd, $ n > m$. It is shown that each prime is a factor of some $ {F_{b,m}}$ for approximately $ 1/k$ bases b, independent of n. Divisors of generalized Fermat numbers of base 6, base 10, and base 12 are tabulated. Three new factors of standard Fermat numbers are included.


References [Enhancements On Off] (What's this?)

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Additional Information

DOI: https://doi.org/10.1090/S0025-5718-1995-1270618-1
Article copyright: © Copyright 1995 American Mathematical Society

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