English

A note on gamma triangles and local gamma vectors

Combinatorics 2018-09-05 v1

Abstract

This article introduces Gamma-triangles, which are closely related to and more fundamental than F-triangles and H-triangles that have been used in the combinatorics of cluster complexes. It is proved that Gamma-triangles can be expressed as sums of the local gamma-vectors introduced by Athanasiadis, which themselves refine the local h-vectors attached by Stanley to simplicial subdivisions. Gamma triangles of all cluster complexes are then explicitly computed.

Cite

@article{arxiv.1809.00575,
  title  = {A note on gamma triangles and local gamma vectors},
  author = {Frédéric Chapoton},
  journal= {arXiv preprint arXiv:1809.00575},
  year   = {2018}
}
R2 v1 2026-06-23T03:52:44.046Z