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BOUNDS FOR ODD k-PERFECT NUMBERS

Published online by Cambridge University Press:  21 July 2011

SHI-CHAO CHEN*
Affiliation:
Institute of Applied Mathematics, School of Mathematics and Information Science, Henan University, Kaifeng 475004, PR China (email: schen@henu.edu.cn)
HAO LUO
Affiliation:
Institute of Applied Mathematics, School of Mathematics and Information Science, Henan University, Kaifeng 475004, PR China (email: luohao200681@126.com)
*
For correspondence; e-mail: schen@henu.edu.cn
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Abstract

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Let k≥2 be an integer. A natural number n is called k-perfect if σ(n)=kn. For any integer r≥1, we prove that the number of odd k-perfect numbers with at most r distinct prime factors is bounded by (k−1)4r3.

Type
Research Article
Copyright
Copyright © Australian Mathematical Publishing Association Inc. 2011

Footnotes

Supported by the Natural Science Foundation of China (Grant 11026080) and the Natural Science Foundation of Education Department of Henan Province (Grant 2009A110001).

References

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