The 27th question: Find the smallest real number $\lambda$, such that $\left(a_{1}{ }^{n}+\prod_{i=1}^{n} a_{i}, a_{2}{ }^{n}+\prod_{i=1}^{n} a_{i}, \ldots, a_{n}{ }^{n}+\prod_{i=1}^{n} a_{i}\right) \leq$ $\lambda\left(a_{1}, a_{2}, \ldots, a_{n}\right)^{n}$ holds for any positive odd number $n$ and $n$ positive integers $a_{1}, a_{2}, \ldots, a_{n}$.