The Sign Pattern Problem for Ehrhart Polynomials

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autori principali: Liu, Feihu, Tao, Sihao, Xin, Guoce
Natura: Preprint
Pubblicazione: 2025
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866912733800169472
author Liu, Feihu
Tao, Sihao
Xin, Guoce
author_facet Liu, Feihu
Tao, Sihao
Xin, Guoce
contents We investigate the sign patterns of coefficients in the Ehrhart polynomial of the Cartesian product between the $r$-th pyramid over the Reeve tetrahedron and the hypercube $[0, n]^n$. This investigation yields partial results on the sign pattern problem for Ehrhart polynomials. Moreover, we show that for each dimension $d \geq 4$, there exists a $d$-dimensional integral polytope $\mathcal{P}$ such that arbitrarily many of the low-degree coefficients in the Ehrhart polynomial $i(\mathcal{P}, t)$ are negative, while all higher-degree coefficients are positive. Finally, we establish five embedding theorems that enable the sign pattern of a lower-dimensional integral polytope to be embedded into a higher-dimensional integral polytope in various ways. As an application, we completely resolve the Ehrhart coefficient sign pattern problem for dimensions $d = 7, 8, 9$.
format Preprint
id arxiv_https___arxiv_org_abs_2509_17714
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle The Sign Pattern Problem for Ehrhart Polynomials
Liu, Feihu
Tao, Sihao
Xin, Guoce
Combinatorics
We investigate the sign patterns of coefficients in the Ehrhart polynomial of the Cartesian product between the $r$-th pyramid over the Reeve tetrahedron and the hypercube $[0, n]^n$. This investigation yields partial results on the sign pattern problem for Ehrhart polynomials. Moreover, we show that for each dimension $d \geq 4$, there exists a $d$-dimensional integral polytope $\mathcal{P}$ such that arbitrarily many of the low-degree coefficients in the Ehrhart polynomial $i(\mathcal{P}, t)$ are negative, while all higher-degree coefficients are positive. Finally, we establish five embedding theorems that enable the sign pattern of a lower-dimensional integral polytope to be embedded into a higher-dimensional integral polytope in various ways. As an application, we completely resolve the Ehrhart coefficient sign pattern problem for dimensions $d = 7, 8, 9$.
title The Sign Pattern Problem for Ehrhart Polynomials
topic Combinatorics
url https://arxiv.org/abs/2509.17714