Questions tagged [pattern-avoidance]
The pattern-avoidance tag has no usage guidance.
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questions with no upvoted or accepted answers
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Pattern Avoidance in Poset Permutations
I am not sure if it is appropriate to use MathOverflow to publicize a conjecture, but I think this is an interesting question and I have no real ideas of how to solve it.
A permutation on a $n$-...
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321-avoiding and parity-alternating permutations
It is classical that 321-avoiding permutations are enumerated by the Catalan numbers.
A permutation is parity-alternating if it sends even integers to even integers, and odd integers to odd. I am ...
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The meet of two dominant permutations in weak order of $S_n$
A permutation is called dominant if its Lehmer code is a partition, or equivalently if it avoids the pattern $132$.
I can prove that given a permutation $v\in S_n$, there is a unique dominant ...
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Permutations avoiding a family of consecutive patterns
Let $B=\{1324,14325,154326,1654327,\ldots\}$ be the set of permutation patterns of the form $1(m-1)(m-2)\cdots 2m$ for $m\geq 4$. I'm interested in the set $\mathcal P$ of permutations that avoid all ...