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A note on the Erdős–Straus conjecture

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Abstract

In this note, we consider the Erdős–Straus Diophantine equation

$$\begin{aligned} \frac{c}{n}=\frac{1}{x} + \frac{1}{y} + \frac{1}{z}, \end{aligned}$$

where n and c are positive integers with \(\gcd (n, c) = 1\). We provide a formula for the number f(nc) of all positive integral solutions (xyz) of the equation. In 1948, Erdős and Straus conjectured that \(f(n,4) \ge 1,\) for all integers \(n \ge 2\). Here, we solve the conjecture for a special case of n.

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Acknowledgments

The authors express their gratitude to the referee for the constructive suggestions on an earlier draft of this paper.

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Correspondence to Alain Togbé.

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Subburam, S., Togbé, A. A note on the Erdős–Straus conjecture. Period Math Hung 72, 43–49 (2016). https://doi.org/10.1007/s10998-015-0109-9

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