In 1946, Erdős and Niven proved that no two distinct partial sums of the harmonic series can be equal. In this paper, we extend their result by establishing the analogous property for a generalized harmonic series of the form $ \sum\frac{1}{a+ib} $, where $ a $ and $ b $ are coprime positive integers with $ a > b\ge 1 $.
Citation: Jun Qiu, Hongguang Wu. A generalization of a theorem of Erdős and Niven[J]. AIMS Mathematics, 2026, 11(6): 18835-18844. doi: 10.3934/math.2026766
In 1946, Erdős and Niven proved that no two distinct partial sums of the harmonic series can be equal. In this paper, we extend their result by establishing the analogous property for a generalized harmonic series of the form $ \sum\frac{1}{a+ib} $, where $ a $ and $ b $ are coprime positive integers with $ a > b\ge 1 $.
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