{"title":"Counting r×s rectangles in (Catalan) words","authors":"Sela Fried , Toufik Mansour","doi":"10.1016/j.dam.2025.01.031","DOIUrl":null,"url":null,"abstract":"<div><div>Generalizing previous results, we introduce and study a new statistic on words, that we call rectangle capacity. For two fixed positive integers <span><math><mi>r</mi></math></span> and <span><math><mi>s</mi></math></span>, this statistic counts the number of occurrences of a rectangle of size <span><math><mrow><mi>r</mi><mo>×</mo><mi>s</mi></mrow></math></span> in the bargraph representation of a word. We find the bivariate generating function for the distribution on words of the number of <span><math><mrow><mi>r</mi><mo>×</mo><mi>s</mi></mrow></math></span> rectangles and the generating function for their total number over all words. We also obtain the analog results for Catalan words.</div></div>","PeriodicalId":50573,"journal":{"name":"Discrete Applied Mathematics","volume":"365 ","pages":"Pages 247-259"},"PeriodicalIF":1.0000,"publicationDate":"2025-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Discrete Applied Mathematics","FirstCategoryId":"100","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0166218X25000393","RegionNum":3,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"MATHEMATICS, APPLIED","Score":null,"Total":0}
引用次数: 0
Abstract
Generalizing previous results, we introduce and study a new statistic on words, that we call rectangle capacity. For two fixed positive integers and , this statistic counts the number of occurrences of a rectangle of size in the bargraph representation of a word. We find the bivariate generating function for the distribution on words of the number of rectangles and the generating function for their total number over all words. We also obtain the analog results for Catalan words.
期刊介绍:
The aim of Discrete Applied Mathematics is to bring together research papers in different areas of algorithmic and applicable discrete mathematics as well as applications of combinatorial mathematics to informatics and various areas of science and technology. Contributions presented to the journal can be research papers, short notes, surveys, and possibly research problems. The "Communications" section will be devoted to the fastest possible publication of recent research results that are checked and recommended for publication by a member of the Editorial Board. The journal will also publish a limited number of book announcements as well as proceedings of conferences. These proceedings will be fully refereed and adhere to the normal standards of the journal.
Potential authors are advised to view the journal and the open calls-for-papers of special issues before submitting their manuscripts. Only high-quality, original work that is within the scope of the journal or the targeted special issue will be considered.