The eigenvalue method for cross t-intersecting families

被引：21

作者：

Tokushige, Norihide ^{[1
]}

机构：

[1] Univ Ryukyus, Coll Educ, Nishihara, Okinawa 9030213, Japan

来源：

JOURNAL OF ALGEBRAIC COMBINATORICS | 2013年 / 38卷 / 03期

关键词：

Cross intersecting family; Eigenvalue method; Hoffman-Delsarte bound; THEOREM;

D O I：

10.1007/s10801-012-0419-4

中图分类号：

O1 [数学];

学科分类号：

0701 ; 070101 ;

摘要：

We show that the ErdAs-Ko-Rado inequality for t-intersecting families of k-element subsets of an n-element set can be easily extended to an inequality for cross t-intersecting families by using the eigenvalue method if n is relatively large depending on k and t. The same method applies to the case of t-intersecting families of k-dimensional subspaces of an n-dimensional vector space over a finite field.

引用

页码：653 / 662

页数：10

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