English

The spiders $S(4m+2,\,2m,\,1)$ are $e$-positive

Combinatorics 2025-09-03 v3

Abstract

By using the composition method, we establish the ee-positivity of spiders of the form S(4m+2,2m,1)S(4m+2,\, 2m,\, 1), which was conjectured by Aliniaeifard, van Willigenburg and Wang. Following the divide-and-conquer strategy, we group one or two eJe_J-terms that have positive coefficients with each eIe_I-term that has a negative coefficient, where the compositions JJ are selected to be obtained by rearranging the parts of II, and show the positivity of the sum of those coefficients. Our main contribution is an explicit construction of the injection.

Cite

@article{arxiv.2405.04915,
  title  = {The spiders $S(4m+2,\,2m,\,1)$ are $e$-positive},
  author = {Davion Q. B. Tang and David G. L. Wang and Monica M. Y. Wang},
  journal= {arXiv preprint arXiv:2405.04915},
  year   = {2025}
}

Comments

18 pages, 4 figure

R2 v1 2026-06-28T16:20:31.612Z