Describing free groups, Part II: $Π^{0}_{4}$ hardness and no $Σ_{2}^{0}$ basis
نویسندگان
چکیده
منابع مشابه
Describing free groups
We consider countable free groups of different ranks. For these groups, we investigate computability theoretic complexity of index sets within the class of free groups and within the class of all groups. For a computable free group of infinite rank, we consider the difficulty of finding a basis.
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ژورنال
عنوان ژورنال: Transactions of the American Mathematical Society
سال: 2012
ISSN: 0002-9947,1088-6850
DOI: 10.1090/s0002-9947-2012-05458-4