论文标题
排列中的订单形态双胞胎
Order-isomorphic twins in permutations
论文作者
论文摘要
令$ a_1,\ dotsc,a_n $为$ [n] $的排列。两个不相交的订单 - 同态子序列称为\ emph {twins}。我们表明,$ [n] $的每个置换都包含长度$ω(n^{3/5})$的双胞胎,改善了$ω(n^{1/2})$的微不足道。我们还表明,随机排列包含长度$ω(n^{2/3})$的双胞胎,这很尖锐。
Let $a_1,\dotsc,a_n$ be a permutation of $[n]$. Two disjoint order-isomorphic subsequences are called \emph{twins}. We show that every permutation of $[n]$ contains twins of length $Ω(n^{3/5})$ improving the trivial bound of $Ω(n^{1/2})$. We also show that a random permutation contains twins of length $Ω(n^{2/3})$, which is sharp.