Séminaire Lotharingien de Combinatoire, B10f (1984), 10 pp.
[Formerly: Publ. I.R.M.A. Strasbourg, 1984, 244/S-110, p.
107-116.]
Bruce E. Sagan
Shellability of Exponentional Structures
Abstract.
Let Π(d)n
denote the set of partitions of nd whose
blocks are divisible by d, let
Πn,r denote the set
of vector partitions
of the Cartesian product of r copies of n, and let
χn
denote the set of colored graphs on a vertex set of n
elements. Each of these
sets has a natural partial ordering. We show that each of
these partially ordered sets is shellable, using the notion of
recursive atom
orderings.
The following version is available:
The paper has been finally published under the same title in
Order 3 (1986), 47-54.