Metrizable refinements of group topologies and the pseudo-intersection number
نویسندگان
چکیده
منابع مشابه
Bases and Refinements of Topologies
Let A be a set and let B be a non empty set. Observe that B is non empty. In this article we present several logical schemes. The scheme FraenkelInvolution deals with a non empty set A, subsets B, C of A, and a unary functor F yielding an element of A, and states that: B = {F(a); a ranges over elements of A : a ∈ C} provided the parameters have the following properties: • C = {F(a); a ranges ov...
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In this article we present several logical schemes. The scheme FraenkelInvolution deals with a non empty set A , subsets B, C of A , and a unary functor F yielding an element of A , and states that: B = {F (a);a ranges over elements of A : a ∈ C} provided the following conditions are satisfied: • C = {F (a);a ranges over elements of A : a ∈ B}, and • For every element a of A holds F (F (a)) = a...
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ژورنال
عنوان ژورنال: Topology and its Applications
سال: 2011
ISSN: 0166-8641
DOI: 10.1016/j.topol.2011.04.005