The complements of lower cones of degrees and the degree spectra of structures© 2016, Association for Symbolic Logic.We study Turing
degrees a for which there is a countable
Irreducible, Singular, and Contiguous Degrees© 2017, Springer Science+Business Media, LLC. We study structures of
degrees of stronger
Elementary differences between the (2p)-C. E. and the (2p + 1)-C. E. enumeration degreesIt is proved that the (2p)-
c.
e.
e-degrees are not elementarily equivalent to the (2p + 1)-
c.
e.
e-degrees Q-degrees of n-C.E. setsIn this paper we study Q-
degrees of n-computably enumerable (n-
c.e.) sets. It is proved that n-
c.e Normal Basis of the Maximal Real Subfield of a Circular FieldNormal Basis of the
Maximal Real Subfield of a Circular Field
Strong Degrees of Categoricity and Weak Density© 2020, Pleiades Publishing, Ltd. Abstract: It is well-known that every
c.e. Turing
degree Definable relations in Turing degree structures (
c.
e.) sets and
degrees in the Ershov difference hierarchy. It is proved that the class of all
c.
e