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Accessible Unlicensed Requires Authentication Published by De Gruyter October 20, 2018

Congruences involving alternating harmonic sums modulo pαqβ

Zhongyan Shen and Tianxin Cai
From the journal Mathematica Slovaca


In 2014, Wang and Cai established the following harmonic congruence for any odd prime p and positive integer r,


where Pn denote the set of positive integers which are prime to n.

In this note, we obtain the congruences for distinct odd primes p, q and positive integers α, β,




  1. Communicated by Federico Pellarin


The authors would like to thank the referee for his/her valuable comments and suggestions, and also the authors thank the China Scholarship Council for supporting our research.


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Received: 2017-01-02
Accepted: 2017-05-30
Published Online: 2018-10-20
Published in Print: 2018-10-25

© 2018 Mathematical Institute Slovak Academy of Sciences