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Related papers: Pattern Avoidance in Set Partitions

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In this work, we study type B set partitions for a given specific positive integer $k$ defined over $\langle n\rangle=\{-n, -(n-1),\cdots -1,0,1,\cdots n-1,n\}$. We found a few generating functions of type B analogue for some of the set…

Combinatorics · Mathematics 2024-04-24 Amrita Acharyya

We investigate pattern-avoiding (0,1)-matrices as generalizations of pattern-avoiding permutations. Our emphasis is on 123-avoiding and 321-avoiding patterns for which we obtain exact results as to the maximum number of 1's such matrices…

Combinatorics · Mathematics 2020-05-06 Richard A. Brualdi , Lei Cao

We study the problem of sequential prediction in the stochastic setting with an adversary that is allowed to inject clean-label adversarial (or out-of-distribution) examples. Algorithms designed to handle purely stochastic data tend to fail…

Machine Learning · Computer Science 2024-01-26 Surbhi Goel , Steve Hanneke , Shay Moran , Abhishek Shetty

In this paper, we study pattern avoidance in weak ascent sequences, giving some results for patterns of length 3. This is an analogous study to one given by Duncan and Steingr\'imsson (2011) for ascent sequences. More precisely, we provide…

Combinatorics · Mathematics 2024-09-04 Beáta Bényi , Toufik Mansour , José L. Ramírez

We study the generating function of the excess number of Rogers-Ramanujan partitions with odd rank over those with even rank, and, using combinatorial and analytical techniques, show that this generating function is closely connected with…

Combinatorics · Mathematics 2025-08-07 Atul Dixit , Gaurav Kumar , Aviral Srivastava

Patience Sorting is a combinatorial algorithm that can be viewed as an iterated, non-recursive form of the Schensted Insertion Algorithm. In recent work the authors have shown that Patience Sorting provides an algorithmic description for…

Combinatorics · Mathematics 2007-05-23 Alexander Burstein , Isaiah Lankham

A branching process in random environment $(Z_n, n \in \N)$ is a generalization of Galton Watson processes where at each generation the reproduction law is picked randomly. In this paper we give several results which belong to the class of…

Probability · Mathematics 2008-12-15 Vincent Bansaye , Julien Berestycki

Class imbalance poses a challenge for developing unbiased, accurate predictive models. In particular, in image segmentation neural networks may overfit to the foreground samples from small structures, which are often heavily…

Computer Vision and Pattern Recognition · Computer Science 2021-02-23 Zeju Li , Konstantinos Kamnitsas , Ben Glocker

Finding distributions of statistics in pattern-avoiding permutations has attracted significant attention in the literature. In particular, Chen, Kitaev, and Zhang derived functional equations for the joint distributions of any subset of…

Combinatorics · Mathematics 2025-09-19 Alice L. L. Gao , Sergey Kitaev , Ya-Xing Li , Xuan Ruan

Mesh patterns are a generalization of classical permutation patterns that encompass classical, bivincular, Bruhat-restricted patterns, and some barred patterns. In this paper, we describe all mesh patterns whose avoidance is coincident with…

Combinatorics · Mathematics 2013-08-28 Bridget Eileen Tenner

We introduce a new boundedness condition for affine permutations, motivated by the fruitful concept of periodic boundary conditions in statistical physics. We study pattern avoidance in bounded affine permutations. In particular, we show…

Combinatorics · Mathematics 2023-06-22 Neal Madras , Justin M. Troyka

Statistical quality control in semiconductor manufacturing hinges on effective diagnostics of wafer bin maps, wherein a key challenge is to detect how defective chips tend to spatially cluster on a wafer--a problem known as spatial pattern…

Applications · Statistics 2021-03-01 Ahmed Aziz Ezzat , Sheng Liu , Dorit S. Hochbaum , Yu Ding

In this paper, we study the Wilf-type equivalence relations among multiset permutations. We identify all multiset equivalences among pairs of patterns consisting of a pattern of length three and another pattern of length at most four. To…

Combinatorics · Mathematics 2021-11-12 Vít Jelínek , Toufik Mansour , José L. Ramírez , Mark Shattuck

We initiate the study of limit shapes for random permutations avoiding a given pattern. Specifically, for patterns of length 3, we obtain delicate results on the asymptotics of distributions of positions of numbers in the permutations. We…

Combinatorics · Mathematics 2013-12-02 Sam Miner , Igor Pak

The study of pattern containment and avoidance for linear permutations is a well-established area of enumerative combinatorics. A cyclic permutation is the set of all rotations of a linear permutation. Callan initiated the study of…

Let $A_k$ be the set of permutations in the symmetric group $S_k$ with prefix 12. This paper concerns the enumeration of involutions which avoid the set of patterns $A_k$. We present a bijection between symmetric Schroder paths of length…

Combinatorics · Mathematics 2008-10-30 Eva Y. P. Deng , Mark Dukes , Toufik Mansour , Susan Y. J. Wu

We characterize separable multidimensional permutations in terms of forbidden patterns and enumerate them by means of generating function, recursive formula and explicit formula. We find a connection between multidimensional permutations…

Combinatorics · Mathematics 2008-03-25 Andrei Asinowski , Toufik Mansour

We study the distribution and the popularity of left children on sets of treeshelves avoiding a pattern of size three. (Treeshelves are ordered binary increasing trees where every child is connected to its parent by a left or a right link.)…

Discrete Mathematics · Computer Science 2016-11-24 Jean-Luc Baril , Sergey Kirgizov , Vincent Vajnovszki

We enumerate and characterize some classes of alternating and reverse alternating involutions avoiding a single pattern of length three or four. If on one hand the case of patterns of length three is trivial, on the other hand, the length…

Combinatorics · Mathematics 2022-09-20 Marilena Barnabei , Flavio Bonetti , Niccolò Castronuovo , Matteo Silimbani

We study the restricted growth function associated with set partitions, and obtain exact formulas for the number of strong records with height one, the total of record heights over set of partitions, and the number of partitions with a…

Combinatorics · Mathematics 2019-08-05 Toufik Mansour , Reza Rastegar , Alexander Roitershtein