English

The short toric polynomial

Combinatorics 2014-06-10 v3

Abstract

We introduce the short toric polynomial associated to a graded Eulerian poset. This polynomial contains the same information as the two toric polynomials introduced by Stanley, but allows different algebraic manipulations. The intertwined recurrence defining Stanley's toric polynomials may be replaced by a single recurrence, in which the degree of the discarded terms is independent of the rank. A short toric variant of the formula by Bayer and Ehrenborg, expressing the toric hh-vector in terms of the cdcd-index, may be stated in a rank-independent form, and it may be shown using weighted lattice path enumeration and the reflection principle. We use our techniques to derive a formula expressing the toric hh-vector of a dual simplicial Eulerian poset in terms of its ff-vector. This formula implies Gessel's formula for the toric hh-vector of a cube, and may be used to prove that the nonnegativity of the toric hh-vector of a simple polytope is a consequence of the Generalized Lower Bound Theorem holding for simplicial polytopes.

Keywords

Cite

@article{arxiv.1008.4433,
  title  = {The short toric polynomial},
  author = {Gábor Hetyei},
  journal= {arXiv preprint arXiv:1008.4433},
  year   = {2014}
}

Comments

Minor corrections

R2 v1 2026-06-21T16:05:22.093Z