%0 Journal Article %T A characterization of those automata that structurally generate finite groups %A Ines Klimann %A Matthieu Picantin %J Mathematics %D 2013 %I arXiv %X Antonenko and Russyev independently have shown that any Mealy automaton with no cycles with exit--that is, where every cycle in the underlying directed graph is a sink component--generates a fi- nite (semi)group, regardless of the choice of the production functions. Antonenko has proved that this constitutes a characterization in the non-invertible case and asked for the invertible case, which is proved in this paper. %U http://arxiv.org/abs/1310.7137v1