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On Property B of Families of Sets

Published online by Cambridge University Press:  20 November 2018

H. L. Abbott
Affiliation:
Department of Mathematics, The University of Alberta, Edmonton, Alberta, T6G 2G1
A. C. Liu
Affiliation:
Department of Mathematics, The University of Alberta, Edmonton, Alberta, T6G 2G1
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A family of sets is said to have property B if there exists a set S such that S∩F≠ ϕ and SF for all F . S is called a B-set for . Let n≥2 and N≥2n-1. Let V = { 1, 2,≠, N} and let = {G:G⊂ V, |G| = rc}. Erdös [3] defined mN(n) to be the size of a smallest subfamily of which does not have property B and proved the following results:

Type
Research Article
Copyright
Copyright © Canadian Mathematical Society 1980

References

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