English

Worpitzky-compatible subarrangements of braid arrangements and cocomparability graphs

Combinatorics 2022-01-26 v1

Abstract

The class of Worpitzky-compatible subarrangements of a Weyl arrangement together with an associated Eulerian polynomial was recently introduced by Ashraf, Yoshinaga and the first author, which brings the characteristic and Ehrhart quasi-polynomials into one formula. The subarrangements of the braid arrangement, the Weyl arrangement of type AA, are known as the graphic arrangements. We prove that the Worpitzky-compatible graphic arrangements are characterized by cocomparability graphs. Our main result yields new formulas for the chromatic and graphic Eulerian polynomials of cocomparability graphs.

Keywords

Cite

@article{arxiv.2007.01248,
  title  = {Worpitzky-compatible subarrangements of braid arrangements and cocomparability graphs},
  author = {Tan Nhat Tran and Akiyoshi Tsuchiya},
  journal= {arXiv preprint arXiv:2007.01248},
  year   = {2022}
}

Comments

11 pages, comments are welcome!