Characterizing strong countable-dimensionality in terms of Baire category
نویسندگان
چکیده
منابع مشابه
Strong characterizing sequences of countable groups
András Biró and Vera Sós prove that for any subgroup G of T generated freely by finitely many generators there is a sequence A ⊆ N such that for all β ∈ T we have (‖.‖ denotes the distance to the nearest integer) β ∈ G ⇒ ∑ n∈A ‖nβ‖ < ∞, β / ∈ G ⇒ lim sup n∈A,n→∞ ‖nβ‖ > 0. We extend this result to arbitrary countable subgroups of T. We also show that not only the sum of norms but the sum of arbi...
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ژورنال
عنوان ژورنال: Fundamenta Mathematicae
سال: 1988
ISSN: 0016-2736,1730-6329
DOI: 10.4064/fm-131-2-155-165