关于一个附加条件的Baranyai定理

IF 0.5 4区 数学 Q3 MATHEMATICS
Gyula O. H. Katona, Gyula Y. Katona
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H. Katona,&nbsp;Gyula Y. Katona\",\"doi\":\"10.1002/jcd.21992\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div>\\n \\n <p>A <span></span><math>\\n <semantics>\\n <mrow>\\n \\n <mrow>\\n <mrow>\\n <mo>(</mo>\\n \\n <mrow>\\n <mi>k</mi>\\n \\n <mo>,</mo>\\n \\n <mi>ℓ</mi>\\n </mrow>\\n \\n <mo>)</mo>\\n </mrow>\\n </mrow>\\n </mrow>\\n </semantics></math> partial partition of an <span></span><math>\\n <semantics>\\n <mrow>\\n \\n <mrow>\\n <mi>n</mi>\\n </mrow>\\n </mrow>\\n </semantics></math>-element set is a collection of <span></span><math>\\n <semantics>\\n <mrow>\\n \\n <mrow>\\n <mi>ℓ</mi>\\n </mrow>\\n </mrow>\\n </semantics></math> pairwise disjoint <span></span><math>\\n <semantics>\\n <mrow>\\n \\n <mrow>\\n <mi>k</mi>\\n </mrow>\\n </mrow>\\n </semantics></math>-element subsets. 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引用次数: 0

摘要

A (k)一个n元素集合的偏分是一个集合成对不相交的k元素子集。证明了,如果n足够大,我们可以找到n k∕n这样的部分分区,如果a1和a2是其中一个部分分区中的不同类,b1和b2在另一个例子中是不同的类,然后其中一个交叉口a1∩b1,a2∩b2的大小不超过k2 .
本文章由计算机程序翻译,如有差异,请以英文原文为准。
Toward a Baranyai Theorem With an Additional Condition

A ( k , ) partial partition of an n -element set is a collection of pairwise disjoint k -element subsets. It is proved that, if n is large enough, one can find n k such partial partitions in such a way that if A 1 and A 2 are distinct classes in one of the partial partitions, B 1 and B 2 are distinct classes in another one, then one of the intersections A 1 B 1 , A 2 B 2 has size at most k 2 .

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来源期刊
CiteScore
1.60
自引率
14.30%
发文量
55
审稿时长
>12 weeks
期刊介绍: The Journal of Combinatorial Designs is an international journal devoted to the timely publication of the most influential papers in the area of combinatorial design theory. All topics in design theory, and in which design theory has important applications, are covered, including: block designs, t-designs, pairwise balanced designs and group divisible designs Latin squares, quasigroups, and related algebras computational methods in design theory construction methods applications in computer science, experimental design theory, and coding theory graph decompositions, factorizations, and design-theoretic techniques in graph theory and extremal combinatorics finite geometry and its relation with design theory. algebraic aspects of design theory. Researchers and scientists can depend on the Journal of Combinatorial Designs for the most recent developments in this rapidly growing field, and to provide a forum for both theoretical research and applications. All papers appearing in the Journal of Combinatorial Designs are carefully peer refereed.
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