fact: Definition step {n} (M:TM n) : mconfig (state M) n -> mconfig (state M) n := fun c => let (news,actions) := trans (cstate c, current_chars (ctapes c)) in mk_mconfig news (doAct_multi (ctapes c) actions).
imports: Undecidability.Shared.Libs.PSL.Vectors.Vectors Undecidability.TM.TM