Symbolic representation for a class of unimodal cycles

A class of unimodal cycles is described, for which every cycle in the class is forced by every unimodal cycle not in the class. Each cycle in the class is assigned a unique symbolic representation as a finite string of Hʹs and Lʹs. A natural process of stacking domino-like blocks is given that constructs all cycles in this class. An algorithm is given to determine when a finite string of Hʹs and Lʹs is the symbolic representation for a cycle in the class.