On the Borel Families of Subsets of Topological Spaces
نویسنده
چکیده
Let T be a 1-sorted structure. The functor TotFamT yielding a family of subsets of T is defined by: (Def. 1) TotFamT = 2 carrier of T . The following proposition is true (1) For every set T and for every family F of subsets of T holds F is countable iff F c is countable. Let us note that Q is countable. The scheme FraenCoun11 concerns a unary predicate P, and states that: {{n};n ranges over elements of Q: P[n]} is countable
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تاریخ انتشار 2007