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On representing sets of an almost disjoint family of sets

Published online by Cambridge University Press:  24 October 2008

P. Komjath
Affiliation:
R. Eötvös University, Budapest 1775, Hungary
E. C. Milner
Affiliation:
University of Calgary, Calgary, Alta. T2N 1N4, Canada

Extract

For cardinal numbers λ, K, ∑ a (λ, K)-family is a family of sets such that || = and |A| = K for every A ε , and a (λ, K, ∑)-family is a (λ,K)-family such that |∪| = ∑. Two sets A, B are said to be almost disjoint if

and an almost disjoint family of sets is a family whose members are pairwise almost disjoint. A representing set of a family is a set X ⊆ ∪ such that XA = ⊘ for each A ε . If is a family of sets and |∪| = ∑, then we write εADR() to signify that is an almost disjoint family of ∑-sized representing sets of . Also, we define a cardinal number

Type
Research Article
Copyright
Copyright © Cambridge Philosophical Society 1987

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References

REFERENCES

[1]Balanda, K. P.. Almost disjoint families of representing sets, Ph.D. Thesis, University of Queensland, 1982.Google Scholar
[2]Balanda, K. P.. Maximally almost disjoint families of representing sets. Math. Proc. Cambridge Philos. Soc. 93 (1983), 17.CrossRefGoogle Scholar
[3]Balanda, K. P.. Almost disjoint families of representing sets. Z. Math. Logik Grundlag. Math. 31 (1985), 7177.CrossRefGoogle Scholar
[4]Erdös, P., Hajnal, A. and Milner, E. C.. On sets of almost disjoint subsets of a set. Acta Math. Acad. Sci. Hungar. 19 (1968), 209218.CrossRefGoogle Scholar
[5]Erdös, P. and Hechler, S. H.. On maximal almost disjoint families over singular cardinals. In Infinite and Finite Sets (ed. Hajnal, A. et al. ), Colloq. Math. Janos Bolyai, vol. 10 (North-Holland, 1975), 597604.Google Scholar
[6]Milner, E. C.. Transversals of disjoint sets. J. London Math. Soc. 43 (1968), 495500.CrossRefGoogle Scholar
[7]Silver, J. H.. The independence of Kurepa's hypothesis and two cardinal conjectures in Model Theory. In Axiomatic Set Theory (ed. Scott, D. S.). Proc. Sympos. Pure Math., vol. 13, part 1 (Amer. Math. Soc., 1971), 383390.CrossRefGoogle Scholar
[8]Tarski, A.. Sur la décomposition des ensembles en sous ensembles presque disjoints. Fund. Math. 12 (1928), 188205 and 14 (1929), 205215.CrossRefGoogle Scholar