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A note on the union-closed sets conjecture

Part of: Combinatorics

Published online by Cambridge University Press:  09 April 2009

Giovanni Lo Faro
Giovanni Lo Faro
Affiliation:
Dipartimento di Matematica, Università di Messina, Contrada Papardo—Salita Sperone, 31 98166 Sant' Agata, Messina, Italy
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Abstract

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It has been conjectured that for any union-closed set there exists some element which is contained in at least half the sets in . It is shown that this conjecture is true if the number of sets in is less than 25. Several conditions on a counterexample are also obtained.

Keywords

setsunion-closed.

MSC classification

Secondary: 05A05: Permutations, words, matrices 05A99: None of the above, but in this section
Type
Research Article
Information
Journal of the Australian Mathematical Society , Volume 57 , Issue 2 , October 1994 , pp. 230 - 236
Copyright
Copyright © Australian Mathematical Society 1994

References

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