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Partitioned transversals

Published online by Cambridge University Press:  18 May 2009

L. Mirsky
Affiliation:
University of Sheffield
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Let E be a finite set and let = (Al, …, A2) be a family of subsets of E. A subset T of E iscalled a transversal of if there exists a bijection Φ: T → {l, …, n} such that xAψ(x) for all x ∈ T. If I ⊆ {1, …, n}, we shall, for brevity, write

(and similarly for families denoted by other letters). The cardinal of a set S will be denoted by |S|. If λ is a non-negative integer, we define λS as S or Ø according as λ > 0 or λ = 0.

Type
Research Article
Copyright
Copyright © Glasgow Mathematical Journal Trust 1974

References

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