On diamond-free subposets of the Boolean lattice

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On diamond-free subposets of the Boolean lattice

The Boolean lattice of dimension two, also known as the diamond, consists of four distinct elements with the following property: A ⊂ B,C ⊂ D. A diamondfree family in the n-dimensional Boolean lattice is a subposet such that no four elements form a diamond. Note that elements B and C may or may not be related. There is a diamond-free family in the n-dimensional Boolean lattice of size (2−o(1)) (...

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ژورنال

عنوان ژورنال: Journal of Combinatorial Theory, Series A

سال: 2013

ISSN: 0097-3165

DOI: 10.1016/j.jcta.2012.11.002