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ω-CHANGE RANDOMNESS AND WEAK DEMUTH RANDOMNESS

Published online by Cambridge University Press:  18 August 2014

JOHANNA N. Y. FRANKLIN
Affiliation:
DEPARTMENT OF MATHEMATICS 196 AUDITORIUM ROAD UNIVERSITY OF CONNECTICUT, U-3009 STORRS, CT 06269-3009, USAE-mail: johanna.franklin@uconn.edu
KENG MENG NG
Affiliation:
SCHOOL OF PHYSICAL & MATHEMATICAL SCIENCES NANYANG TECHNOLOGICAL UNIVERSITY 21 NANYANG LINK SINGAPOREE-mail: kmng@ntu.edu.sg

Abstract

We extend our work on difference randomness. Each component of a difference test is a Boolean combination of two r.e. open sets; here we consider tests in which the kth component is a Boolean combination of g(k) r.e. open sets for a given recursive function g. We use this method to produce an alternate characterization of weak Demuth randomness in terms of these tests and further show that a real is weakly Demuth random if and only if it is Martin-Löf random and cannot compute a strongly prompt r.e. set. We conclude with a study of related lowness notions and obtain as a corollary that lowness for balanced randomness is equivalent to being recursive.

Type
Articles
Copyright
Copyright © The Association for Symbolic Logic 2014 

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References

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