Antichains and counterpoint dichotomies
  We construct a special type of antichain (i. e., a family of subsets of a set, such that no subset is contained in another) using group-theoretical considerations, and obtain an upper bound on the cardinality of such an antichain. We apply the result to bound the number of strong counterpoint dichotomies up to affine isomorphisms. 
Octavio A. Agust\'in-Aquino
math.CO math.GR