English

Parallel edges in ribbon graphs and interpolating behavior of partial-duality polynomials

Combinatorics 2021-11-11 v2

Abstract

Recently, Gross, Mansour and Tucker introduced the partial-twuality polynomials. In this paper, we find that when there are enough parallel edges, any multiple graph is a negative answer to the problem 8.7 in their paper [European J. Combin. 95 (2021), 103329]: Is the restricted-orientable partial-Petrial polynomial of an arbitrary ribbon graph even-interpolating? In addition, we also find a counterexample to the conjecture 8.1 of Gross, Mansour and Tucker: If the partial-dual genus polynomial is neither an odd nor an even polynomial, then it is interpolating.

Keywords

Cite

@article{arxiv.2106.00381,
  title  = {Parallel edges in ribbon graphs and interpolating behavior of partial-duality polynomials},
  author = {Qiyao Chen and Yichao Chen},
  journal= {arXiv preprint arXiv:2106.00381},
  year   = {2021}
}
R2 v1 2026-06-24T02:42:08.726Z