Recursion theoretic operators and morphisms on numbered sets
Representability of recursive P. Martin-Löf tests
Restrictions on the degree spectra of algebraic structures.
Results on automorphisms of recursively saturated models of PA
Reverse mathematics of some topics from algorithmic graph theory
This paper analyzes the proof-theoretic strength of an infinite version of several theorems from algorithmic graph theory. In particular, theorems on reachability matrices, shortest path matrices, topological sorting, and minimal spanning trees are considered.