We consider the class of so-called k-quasidiscrete linear orderings, show that every k-quasi-discrete ordering of low degree has a computable representation, and study estimates for the complexity of all isomorphisms ...
We say that L is weakly η-like if L/∼ is isomorphic to the natural ordering of rational numbers. We construct a computable presentation of any low weakly η-like linear ordering with no strongly η-like interval. Also we ...