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Infinite Classes of Covering Numbers

Published online by Cambridge University Press:  20 November 2018

I. Bluskov
Affiliation:
Department of Mathematics and Computer Science, University of Northern British Columbia, Prince George, BC, V2N 5M2, email: [email protected]
M. Greig
Affiliation:
Greig Consulting, 207-170 East Fifth Street, North Vancouver, BC, V7L 4L4, email: [email protected]
K. Heinrich
Affiliation:
University of Regina, Regina, Saskatchewan, S4S 0A2, email: [email protected]
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Abstract

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Let $D$ be a family of $k$-subsets (called blocks) of a $v$-set $X\left( v \right)$. Then $D$ is a $\left( v,\,k,\,t \right)$ covering design or covering if every $t$-subset of $X\left( v \right)$ is contained in at least one block of $D$. The number of blocks is the size of the covering, and the minimum size of the covering is called the covering number. In this paper we consider the case $t\,=\,2$, and find several infinite classes of covering numbers. We also give upper bounds on other classes of covering numbers.

Keywords

Type
Research Article
Copyright
Copyright © Canadian Mathematical Society 2000

References

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