parmenides51 wrote: Given a positive integer $n \ge 3$. Find the smallest real number $k$ such that for any positive real number except $a_1, a_2,..,a_n$, $$\sum_{i=1}^{n-1}\frac{a_i}{ s-a_i}+\frac{ka_n}{s-a_n} \ge \frac{n-1}{n-2}$$where, $s=a_1+a_2+..+a_n$ $$k_{min}=\left(\frac{n-1}{n-2}\right)^2$$

parmenides51 wrote: Given a positive integer $n \ge 3$. Find the smallest real number $k$ such that for any positive real number except $a_1, a_2,..,a_n$, $$\sum_{i=1}^{n-1}\frac{a_i}{ s-a_i}+\frac{ka_n}{s-a_n} \ge \frac{n-1}{n-2}$$where, $s=a_1+a_2+..+a_n$ Who is the author?

@above problem by 赵斌 = Zhao Bin

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