The combinatorics of interval-vector polytopes

Abstract

An \emph{interval vector} is a $(0,1)$-vector in ${\mathbb{R}}^n$ for which all the 1's appear consecutively, and an \emph{interval-vector polytope} is the convex hull of a set of interval vectors in ${\mathbb{R}}^n$. We study three particular classes of interval vector polytopes which exhibit interesting geometric-combinatorial structures; e.g., one class has volumes equal to the Catalan numbers, whereas another class has face numbers given by the Pascal 3-triangle.

10 pages, 3 figures