On group automata over finite fields

We investigate the structure of incidence rings of group automata over finite fields. One of the major tools used in research on the structure of ring constructions is the Jacobson radical. Our main theorem gives a complete description of the Jacobson radicals of incidence rings of (possibly nondeterministic) group automata over finite fields in the important special case where the input group is abelian. © 2003 Elsevier Inc. All rights reserved.