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