Computational complexity of recursively enumerable sets
نویسندگان
چکیده
منابع مشابه
Kolmogorov Complexity and Instance Complexity of Recursively Enumerable Sets
We study in which way Kolmogorov complexity and instance complexity affect properties of r.e. sets. We show that the well-known 2 log n upper bound on the Kolmogorov complexity of initial segments of r.e. sets is optimal and characterize the T-degrees of r.e. sets which attain this bound. The main part of the paper is concerned with instance complexity of r.e. sets. We construct a nonrecursive ...
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For given sets A, B, and Z of natural numbers where the members of Z are z0, z1, . . . in ascending order, one says that A is selected from B by Z if A(i) = B(zi) for all i. Furthermore, say that A is selected from B if A is selected from B by some recursively enumerable set, and that A is selected from B in n steps iff there are sets E0, E1, . . . , En such that E0 = A, En = B, and Ei is selec...
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This paper presents some new theorems concerning recursively enumerable (r.e.) sets. The aim of the paper is to advance the search for a decision procedure for the elementary theory of r.e. sets. More precisely, an effective method is sought for deciding whether or not an arbitrary sentence formulated in the lower predicate calculus with sole relative symbol £ is true of the r.e. sets. The main...
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ژورنال
عنوان ژورنال: Information and Control
سال: 1982
ISSN: 0019-9958
DOI: 10.1016/s0019-9958(82)80082-x