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A NEW UPPER BOUND FOR THE SUM OF DIVISORS FUNCTION

Part of: Elementary number theory Computational number theory

Published online by Cambridge University Press:  14 August 2017

CHRISTIAN AXLER Open the ORCID record for CHRISTIAN AXLER [Opens in a new window]
CHRISTIAN AXLER*
Affiliation:
Institute of Mathematics, Heinrich Heine University, Duesseldorf, 40225 Duesseldorf, Germany email [email protected]
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Abstract

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Robin’s criterion states that the Riemann hypothesis is true if and only if $\unicode[STIX]{x1D70E}(n)<e^{\unicode[STIX]{x1D6FE}}n\log \log n$ for every positive integer $n\geq 5041$. In this paper we establish a new unconditional upper bound for the sum of divisors function, which improves the current best unconditional estimate given by Robin. For this purpose, we use a precise approximation for Chebyshev’s $\unicode[STIX]{x1D717}$-function.

Keywords

Riemann hypothesisRobin’s inequalitysum of divisors function

MSC classification

Primary: 11A25: Arithmetic functions; related numbers; inversion formulas
Secondary: 11Y70: Values of arithmetic functions; tables
Type
Research Article
Information
Bulletin of the Australian Mathematical Society , Volume 96 , Issue 3 , December 2017 , pp. 374 - 379
Copyright
© 2017 Australian Mathematical Publishing Association Inc. 

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