We prove that the group of reversible cellular automata (RCA), on any alphabet $A$, contains a subgroup generated by three involutions which an isomorphic copy every finitely RCA $B$. This result follows from

In this paper, we formalize precisely the sense in which application of a cellular automaton to partial configurations is natural extension its local transition function through categorical notion Kan extension. fact, two possible ways do such an and ingredients involved their definition are related extensions many ways. These relations provide additional links between computer science category...