Variants of the Damascus inequality

In 2016, Dannan and Sitnik established the notable Damascus inequality, which features a symmetric structure under a multiplicative constraint. In this study, we consider the natural generalisation of this inequality by characterising all positive integers $m$ and $n$ such that the inequality $$\sum _{j=1}^m\frac{x_j^n-1}{x_j^{n+1}+1}⩽0$$ holds for any positive real numbers $x_1,\dots ,x_m$ with ${\prod }_{j=1}^m{x}_j=1$. Our approach relies on the theories of GA-convexity and Sturm’s sequence. For the cases where the inequality fails, we also investigate the topological properties of the set of non-solutions.