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We give a construction of r-partite r-uniform intersecting hypergraphs with cover number at least r − 4 for all but finitely many r. This answers a question of Abu-Khazneh, Barát, Pokrovskiy and Szabó, and shows that a long-standing unsolved conjecture due to Ryser is close to being best possible for every value of r.
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ژورنال
عنوان ژورنال: Bulletin of the American Mathematical Society
سال: 2014
ISSN: 0273-0979,1088-9485
DOI: 10.1090/s0273-0979-2014-01451-x