Co-total Enumeration Degrees

Abstract

This paper is dedicated to the study of the enumeration degrees which contain sets the complements of which are the graphs of some total functions. Such e-degrees are called co-total. That every total e-degree a≥0′ e contains such total function f that ${\rm deg}_e(\overline{{\rm graph}(f)})$ is a quasi-minimal e-degree has been proved. Some known results of McEvoy and Gutteridge with the aid of co-total e-degrees become stronger as well.