Recursive labelling systems and stability of recursive structures in hyperarithmetical degrees
نویسندگان
چکیده
منابع مشابه
Recursive Labelling Systems and Stability of Recursive Structures in Hyperarithmetical Degrees
We show that, under certain assumptions of recursiveness in 21, the recursive structure 21 is A^-stable for a < wfK if and only if there is an enumeration of 21 using a E^ set of recursive EQ infinitary formulae and finitely many parameters from 21. This extends the results of [1]. To do this, we first obtain results concerning A^ paths in recursive labelling systems, also extending results of ...
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ژورنال
عنوان ژورنال: Transactions of the American Mathematical Society
سال: 1986
ISSN: 0002-9947
DOI: 10.1090/s0002-9947-1986-0860377-7