{"title":"研究了幂LCM矩阵在GCD闭集上被幂GCD矩阵可整除的问题","authors":"Jianrong Zhao , Chenxu Wang , Yu Fu","doi":"10.1016/j.jcta.2025.106063","DOIUrl":null,"url":null,"abstract":"<div><div>Let <span><math><mi>S</mi><mo>=</mo><mo>{</mo><msub><mrow><mi>x</mi></mrow><mrow><mn>1</mn></mrow></msub><mo>,</mo><mo>…</mo><mo>,</mo><msub><mrow><mi>x</mi></mrow><mrow><mi>n</mi></mrow></msub><mo>}</mo></math></span> be a gcd-closed set (i.e. <span><math><mo>(</mo><msub><mrow><mi>x</mi></mrow><mrow><mi>i</mi></mrow></msub><mo>,</mo><msub><mrow><mi>x</mi></mrow><mrow><mi>j</mi></mrow></msub><mo>)</mo><mo>∈</mo><mi>S</mi></math></span> for all <span><math><mn>1</mn><mo>≤</mo><mi>i</mi><mo>,</mo><mi>j</mi><mo>≤</mo><mi>n</mi></math></span>). In 2002, Hong proposed the divisibility problem of characterizing all gcd-closed sets <em>S</em> with <span><math><mo>|</mo><mi>S</mi><mo>|</mo><mo>≥</mo><mn>4</mn></math></span> such that the GCD matrix (<em>S</em>) divides the LCM matrix <span><math><mo>[</mo><mi>S</mi><mo>]</mo></math></span> in the ring <span><math><msub><mrow><mi>M</mi></mrow><mrow><mi>n</mi></mrow></msub><mo>(</mo><mi>Z</mi><mo>)</mo></math></span>. For <span><math><mi>x</mi><mo>∈</mo><mi>S</mi></math></span>, let <span><math><msub><mrow><mi>G</mi></mrow><mrow><mi>S</mi></mrow></msub><mo>(</mo><mi>x</mi><mo>)</mo><mo>:</mo><mo>=</mo><mo>{</mo><mi>z</mi><mo>∈</mo><mi>S</mi><mo>:</mo><mi>z</mi><mo><</mo><mi>x</mi><mo>,</mo><mi>z</mi><mo>|</mo><mi>x</mi><mtext> and </mtext><mo>(</mo><mi>z</mi><mo>|</mo><mi>y</mi><mo>|</mo><mi>x</mi><mo>,</mo><mi>y</mi><mo>∈</mo><mi>S</mi><mo>)</mo><mo>⇒</mo><mi>y</mi><mo>∈</mo><mo>{</mo><mi>z</mi><mo>,</mo><mi>x</mi><mo>}</mo><mo>}</mo></math></span>. In 2009, Feng, Hong and Zhao answered this problem in the context where <span><math><msub><mrow><mi>max</mi></mrow><mrow><mi>x</mi><mo>∈</mo><mi>S</mi></mrow></msub><mo></mo><mo>{</mo><mo>|</mo><msub><mrow><mi>G</mi></mrow><mrow><mi>S</mi></mrow></msub><mo>(</mo><mi>x</mi><mo>)</mo><mo>|</mo><mo>}</mo><mo>≤</mo><mn>2</mn></math></span>. In 2022, Zhao, Chen and Hong obtained a necessary and sufficient condition on the gcd-closed set <em>S</em> with <span><math><msub><mrow><mi>max</mi></mrow><mrow><mi>x</mi><mo>∈</mo><mi>S</mi></mrow></msub><mo></mo><mo>{</mo><mo>|</mo><msub><mrow><mi>G</mi></mrow><mrow><mi>S</mi></mrow></msub><mo>(</mo><mi>x</mi><mo>)</mo><mo>|</mo><mo>}</mo><mo>=</mo><mn>3</mn></math></span> such that <span><math><mo>(</mo><mi>S</mi><mo>)</mo><mo>|</mo><mrow><mo>[</mo><mi>S</mi><mo>]</mo></mrow></math></span>. Meanwhile, they raised a conjecture on the necessary and sufficient condition such that <span><math><mo>(</mo><mi>S</mi><mo>)</mo><mo>|</mo><mrow><mo>[</mo><mi>S</mi><mo>]</mo></mrow></math></span> holds for the remaining case <span><math><msub><mrow><mi>max</mi></mrow><mrow><mi>x</mi><mo>∈</mo><mi>S</mi></mrow></msub><mo></mo><mo>{</mo><mo>|</mo><msub><mrow><mi>G</mi></mrow><mrow><mi>S</mi></mrow></msub><mo>(</mo><mi>x</mi><mo>)</mo><mo>|</mo><mo>}</mo><mo>≥</mo><mn>4</mn></math></span>. In this paper, we confirm the Zhao-Chen-Hong conjecture from a novel perspective, consequently solve Hong's open problem completely.</div></div>","PeriodicalId":50230,"journal":{"name":"Journal of Combinatorial Theory Series A","volume":"215 ","pages":"Article 106063"},"PeriodicalIF":0.9000,"publicationDate":"2025-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Studying the divisibility of power LCM matrices by power GCD matrices on gcd-closed sets\",\"authors\":\"Jianrong Zhao , Chenxu Wang , Yu Fu\",\"doi\":\"10.1016/j.jcta.2025.106063\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><div>Let <span><math><mi>S</mi><mo>=</mo><mo>{</mo><msub><mrow><mi>x</mi></mrow><mrow><mn>1</mn></mrow></msub><mo>,</mo><mo>…</mo><mo>,</mo><msub><mrow><mi>x</mi></mrow><mrow><mi>n</mi></mrow></msub><mo>}</mo></math></span> be a gcd-closed set (i.e. <span><math><mo>(</mo><msub><mrow><mi>x</mi></mrow><mrow><mi>i</mi></mrow></msub><mo>,</mo><msub><mrow><mi>x</mi></mrow><mrow><mi>j</mi></mrow></msub><mo>)</mo><mo>∈</mo><mi>S</mi></math></span> for all <span><math><mn>1</mn><mo>≤</mo><mi>i</mi><mo>,</mo><mi>j</mi><mo>≤</mo><mi>n</mi></math></span>). In 2002, Hong proposed the divisibility problem of characterizing all gcd-closed sets <em>S</em> with <span><math><mo>|</mo><mi>S</mi><mo>|</mo><mo>≥</mo><mn>4</mn></math></span> such that the GCD matrix (<em>S</em>) divides the LCM matrix <span><math><mo>[</mo><mi>S</mi><mo>]</mo></math></span> in the ring <span><math><msub><mrow><mi>M</mi></mrow><mrow><mi>n</mi></mrow></msub><mo>(</mo><mi>Z</mi><mo>)</mo></math></span>. For <span><math><mi>x</mi><mo>∈</mo><mi>S</mi></math></span>, let <span><math><msub><mrow><mi>G</mi></mrow><mrow><mi>S</mi></mrow></msub><mo>(</mo><mi>x</mi><mo>)</mo><mo>:</mo><mo>=</mo><mo>{</mo><mi>z</mi><mo>∈</mo><mi>S</mi><mo>:</mo><mi>z</mi><mo><</mo><mi>x</mi><mo>,</mo><mi>z</mi><mo>|</mo><mi>x</mi><mtext> and </mtext><mo>(</mo><mi>z</mi><mo>|</mo><mi>y</mi><mo>|</mo><mi>x</mi><mo>,</mo><mi>y</mi><mo>∈</mo><mi>S</mi><mo>)</mo><mo>⇒</mo><mi>y</mi><mo>∈</mo><mo>{</mo><mi>z</mi><mo>,</mo><mi>x</mi><mo>}</mo><mo>}</mo></math></span>. In 2009, Feng, Hong and Zhao answered this problem in the context where <span><math><msub><mrow><mi>max</mi></mrow><mrow><mi>x</mi><mo>∈</mo><mi>S</mi></mrow></msub><mo></mo><mo>{</mo><mo>|</mo><msub><mrow><mi>G</mi></mrow><mrow><mi>S</mi></mrow></msub><mo>(</mo><mi>x</mi><mo>)</mo><mo>|</mo><mo>}</mo><mo>≤</mo><mn>2</mn></math></span>. In 2022, Zhao, Chen and Hong obtained a necessary and sufficient condition on the gcd-closed set <em>S</em> with <span><math><msub><mrow><mi>max</mi></mrow><mrow><mi>x</mi><mo>∈</mo><mi>S</mi></mrow></msub><mo></mo><mo>{</mo><mo>|</mo><msub><mrow><mi>G</mi></mrow><mrow><mi>S</mi></mrow></msub><mo>(</mo><mi>x</mi><mo>)</mo><mo>|</mo><mo>}</mo><mo>=</mo><mn>3</mn></math></span> such that <span><math><mo>(</mo><mi>S</mi><mo>)</mo><mo>|</mo><mrow><mo>[</mo><mi>S</mi><mo>]</mo></mrow></math></span>. Meanwhile, they raised a conjecture on the necessary and sufficient condition such that <span><math><mo>(</mo><mi>S</mi><mo>)</mo><mo>|</mo><mrow><mo>[</mo><mi>S</mi><mo>]</mo></mrow></math></span> holds for the remaining case <span><math><msub><mrow><mi>max</mi></mrow><mrow><mi>x</mi><mo>∈</mo><mi>S</mi></mrow></msub><mo></mo><mo>{</mo><mo>|</mo><msub><mrow><mi>G</mi></mrow><mrow><mi>S</mi></mrow></msub><mo>(</mo><mi>x</mi><mo>)</mo><mo>|</mo><mo>}</mo><mo>≥</mo><mn>4</mn></math></span>. In this paper, we confirm the Zhao-Chen-Hong conjecture from a novel perspective, consequently solve Hong's open problem completely.</div></div>\",\"PeriodicalId\":50230,\"journal\":{\"name\":\"Journal of Combinatorial Theory Series A\",\"volume\":\"215 \",\"pages\":\"Article 106063\"},\"PeriodicalIF\":0.9000,\"publicationDate\":\"2025-05-02\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Journal of Combinatorial Theory Series A\",\"FirstCategoryId\":\"100\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0097316525000585\",\"RegionNum\":2,\"RegionCategory\":\"数学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"MATHEMATICS\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Combinatorial Theory Series A","FirstCategoryId":"100","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0097316525000585","RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"MATHEMATICS","Score":null,"Total":0}
引用次数: 0
摘要
设S={x1,…,xn}是一个gcd闭集(即(xi,xj)∈S,对于所有1≤i,j≤n)。2002年,Hong提出了表征所有GCD -闭集S的|S|≥4使得GCD矩阵(S)能除环Mn(Z)中的LCM矩阵[S]的可分性问题。x∈年代,让GS (x): = {z∈年代:z< x, z | x和y z | | x, y∈(S)⇒y∈{z、x}}。2009年,Feng, Hong和Zhao在maxx∈S∈{|GS(x)|}≤2的情况下回答了这个问题。Zhao、Chen和Hong在2022年得到了maxx∈S∈S (|GS(x)|}=3的gcd-闭集S上的一个充要条件,使得(S)|[S]。同时,他们提出了一个关于(S)|[S]对剩余情况maxx∈S∈{|GS(x)|}≥4成立的充分必要条件的猜想。本文从一个全新的角度证实了赵-陈-洪猜想,从而彻底解决了洪的开放问题。
Studying the divisibility of power LCM matrices by power GCD matrices on gcd-closed sets
Let be a gcd-closed set (i.e. for all ). In 2002, Hong proposed the divisibility problem of characterizing all gcd-closed sets S with such that the GCD matrix (S) divides the LCM matrix in the ring . For , let . In 2009, Feng, Hong and Zhao answered this problem in the context where . In 2022, Zhao, Chen and Hong obtained a necessary and sufficient condition on the gcd-closed set S with such that . Meanwhile, they raised a conjecture on the necessary and sufficient condition such that holds for the remaining case . In this paper, we confirm the Zhao-Chen-Hong conjecture from a novel perspective, consequently solve Hong's open problem completely.
期刊介绍:
The Journal of Combinatorial Theory publishes original mathematical research concerned with theoretical and physical aspects of the study of finite and discrete structures in all branches of science. Series A is concerned primarily with structures, designs, and applications of combinatorics and is a valuable tool for mathematicians and computer scientists.