AbstractA family of J of open subsets of the real line is called an ω-cover of a set X iff every finite subset of X is contained in an element of J. A set of reals X is a γ-set iff for every ω-cover J of X there exists 〈Dn: n < ω〉ϵ Jω such that X⊆∪n∩m > n Dm. In this paper we show that assuming Martin's axiom there is a γ-set X of cardinality the continuum
Abstract. Suppose that κ is a regular uncountable cardinal and λ is a car-dinal> κ. We give a dir...
AbstractLet n, m and k be positive integers. Let X be a set of cardinality n, and let F be a family ...
AbstractWe solve four out of the six open problems concerning critical cardinalities of topological ...
AbstractA family of J of open subsets of the real line is called an ω-cover of a set X iff every fin...
A set X ⊆ 2 ω is a λ ′-set iff for every countable set Y ⊆ 2 ω there exists a Gδ set G such that (X ...
In this paper we prove that if there is a Borel-cover γ-set of car-dinality the continuum, then ther...
Abstract. We show that even for subsets X of the real line that do not con-tain perfect sets, the Hu...
In this note it is proved that the least cardinal K such that R cannot be covered by fc many null se...
Abstract: "The existence of exact upper bounds for increasing sequences of ordinal functions modulo ...
Let X be a set, κ be a cardinal number and let H be a family of subsets of X which covers each x ∈ X...
AbstractThe existence of exact upper bounds for increasing sequences of ordinal functions modulo an ...
Abstract. Let S1(Γ,Γ) be the statement: For each sequence of point-cofinite open covers, one can pic...
Given a prime power q, define c (q) as the minimum cardinality of a subset H of F 3 q which satisfie...
Given a prime power q, define c (q) as the minimum cardinality of a subset H of F 3 q which satisfie...
AbstractLet C be a set of cardinals and let X be a (finite or infinite) set. Denote by PC(X) the fam...
Abstract. Suppose that κ is a regular uncountable cardinal and λ is a car-dinal> κ. We give a dir...
AbstractLet n, m and k be positive integers. Let X be a set of cardinality n, and let F be a family ...
AbstractWe solve four out of the six open problems concerning critical cardinalities of topological ...
AbstractA family of J of open subsets of the real line is called an ω-cover of a set X iff every fin...
A set X ⊆ 2 ω is a λ ′-set iff for every countable set Y ⊆ 2 ω there exists a Gδ set G such that (X ...
In this paper we prove that if there is a Borel-cover γ-set of car-dinality the continuum, then ther...
Abstract. We show that even for subsets X of the real line that do not con-tain perfect sets, the Hu...
In this note it is proved that the least cardinal K such that R cannot be covered by fc many null se...
Abstract: "The existence of exact upper bounds for increasing sequences of ordinal functions modulo ...
Let X be a set, κ be a cardinal number and let H be a family of subsets of X which covers each x ∈ X...
AbstractThe existence of exact upper bounds for increasing sequences of ordinal functions modulo an ...
Abstract. Let S1(Γ,Γ) be the statement: For each sequence of point-cofinite open covers, one can pic...
Given a prime power q, define c (q) as the minimum cardinality of a subset H of F 3 q which satisfie...
Given a prime power q, define c (q) as the minimum cardinality of a subset H of F 3 q which satisfie...
AbstractLet C be a set of cardinals and let X be a (finite or infinite) set. Denote by PC(X) the fam...
Abstract. Suppose that κ is a regular uncountable cardinal and λ is a car-dinal> κ. We give a dir...
AbstractLet n, m and k be positive integers. Let X be a set of cardinality n, and let F be a family ...
AbstractWe solve four out of the six open problems concerning critical cardinalities of topological ...
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