Abstract:
Let $S_n$ be the set of all permutations of the numbers $1,2,\dots,n$, and let $l_n(\sigma)$ be the number of terms in the maximal monotonic subsequence contained in $\sigma\in S_n$. If $M(l_n(\sigma))$ is the mean value of $l_n(\sigma)$ on $S_n$, then, for all except a finite number of n, the bound $M(l_n(\sigma))\le e\sqrt n$ is valid.