Reaping number and π-character of Boolean algebras
نویسندگان
چکیده
منابع مشابه
Reaping Numbers of Boolean Algebras
A subsetA of a Boolean algebra B is said to be (n,m)reaped if there is a partition of unity P ⊂ B of size n such that |{b ∈ P : b∧a 6= ∅}| ≥ m for all a ∈ A. The reaping number rn,m(B) of a Boolean algebra B is the minimum cardinality of a set A ⊂ B\ {0} such which cannot be (n,m)-reaped. It is shown that, for each n ∈ ω, there is a Boolean algebra B such that rn+1,2(B) 6= rn,2(B). Also, {rn,m(...
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ژورنال
عنوان ژورنال: Discrete Mathematics
سال: 1992
ISSN: 0012-365X
DOI: 10.1016/0012-365x(92)90654-x