We compare the degrees of enumerability and the closed Medvedev degrees and find that many situations occur. There are nonzero closed degrees that do not bound nonzero degrees of enumerability, there are nonzero degrees of enumerability that do not bound nonzero closed degrees, and there are degrees that are nontrivially both degrees of enumerability and closed degrees. We also show that the compact degrees of enumerability exactly correspond to the cototal enumeration degrees
AbstractWe prove the following three theorems on the enumeration degrees of ∑20 sets. Theorem A: The...
Abstract. A set A is symmetric enumeration (se-) reducible to a set B (A≤seB) if A is enumeration re...
In the paper we present a survey on n-c.e. Turing and e-degrees. Also we discuss some open problems ...
We compare the degrees of enumerability and the closed Medvedev degrees and find that many situation...
We survey some open problems in the enumeration degrees. The problems fall into the following three ...
We study the Medvedev degrees of mass problems with distinguished topological properties, such as de...
We characterize the join-irreducible Medvedev degrees as the degrees of complements of Turing ideals...
AbstractLet Es denote the lattice of Medvedev degrees of non-empty Π10 subsets of 2ω, and let Ew den...
AbstractLachlan observed that any nonzero d.c.e. degree bounds a nonzero c.e. degree. In this paper,...
AbstractThis paper continues the project, initiated in (Arslanov, Cooper and Kalimullin 2003) [3], o...
© 2018, Pleiades Publishing, Ltd. Questions of definability of computably enumerable degrees in the ...
We prove that the first-order theory of the Medvedev degrees, the first-order theory of the Muchnik ...
Abstract. We show that if A and B form a nontrivial K-pair, then there is a semi-computable set C su...
We investigate the complexity of mathematical problems from two perspectives: Medvedev degrees and r...
© 2017, Springer Science+Business Media, LLC. We study structures of degrees of stronger algorithmic...
AbstractWe prove the following three theorems on the enumeration degrees of ∑20 sets. Theorem A: The...
Abstract. A set A is symmetric enumeration (se-) reducible to a set B (A≤seB) if A is enumeration re...
In the paper we present a survey on n-c.e. Turing and e-degrees. Also we discuss some open problems ...
We compare the degrees of enumerability and the closed Medvedev degrees and find that many situation...
We survey some open problems in the enumeration degrees. The problems fall into the following three ...
We study the Medvedev degrees of mass problems with distinguished topological properties, such as de...
We characterize the join-irreducible Medvedev degrees as the degrees of complements of Turing ideals...
AbstractLet Es denote the lattice of Medvedev degrees of non-empty Π10 subsets of 2ω, and let Ew den...
AbstractLachlan observed that any nonzero d.c.e. degree bounds a nonzero c.e. degree. In this paper,...
AbstractThis paper continues the project, initiated in (Arslanov, Cooper and Kalimullin 2003) [3], o...
© 2018, Pleiades Publishing, Ltd. Questions of definability of computably enumerable degrees in the ...
We prove that the first-order theory of the Medvedev degrees, the first-order theory of the Muchnik ...
Abstract. We show that if A and B form a nontrivial K-pair, then there is a semi-computable set C su...
We investigate the complexity of mathematical problems from two perspectives: Medvedev degrees and r...
© 2017, Springer Science+Business Media, LLC. We study structures of degrees of stronger algorithmic...
AbstractWe prove the following three theorems on the enumeration degrees of ∑20 sets. Theorem A: The...
Abstract. A set A is symmetric enumeration (se-) reducible to a set B (A≤seB) if A is enumeration re...
In the paper we present a survey on n-c.e. Turing and e-degrees. Also we discuss some open problems ...