Takayuki Hibi

activity

20242026

O

-sequences

1 citations · 1 across the 11 of their papers we have counts for

collaborators

12 papers

math.AC2026

Edge ideals of gapfree graphs with matching number $3$

Nursel Erey, Tài Huy Hà, Takayuki Hibi +2

We prove that if $G$ is a gapfree graph with matching number $3$ , then every power $I (G)^{q}$ , $q \geq 2$ , of its edge ideal has linear quotients, and hence a linear resolution. Our ap…

math.AC2026

Depth of edge ideals and vertex connectivity of finite graphs

Takayuki Hibi, Seyed Amin Seyed Fakhari

Let $G$ be a finite graph on $[n] := {1, \dots, n}$ and $κ (G)$ its vertex connectivity. Let $S = K [x_{1}, \dots, x_{n}]$ denote the polynomial ring in $n$ variables over a field $K$ an…

math.CO2026

Symmetric and unimodal independence polynomials of trees

Takayuki Hibi, Selvi Kara, Dalena Vien

Given $n \geq 1$ , we study the existence of a tree on $n$ vertices whose independence polynomial is symmetric and unimodal as well as the existence of a symmetric and unimodal inde…

math.CO2026

Independence polynomials of graphs

Takayuki Hibi, Selvi Kara, Dalena Vien

In this paper, we study the independence polynomial $P_{G} (x)$ of a finite simple graph $G$ , with emphasis on the evaluation at $x = - 1$ , symmetry, and its connection with the $h$ -poly…

math.AC2026

Pseudo-Gorenstein $^{*}$ Graphs

Takayuki Hibi, Selvi Kara, Dalena Vien

Motivated by pseudo-Gorenstein rings in commutative algebra, introduced by Herzog et al., we define pseudo-Gorenstein $^{*}$ graphs and classify them in several natural graph famili…

math.AC2025

Binomial edge ideals of Cameron-Walker graphs

Takayuki Hibi, Sara Saeedi Madani

Let $G$ be a Cameron--Walker graph on $n$ vertices and $J_{G}$ the binomial edge ideal of $G$ . Let $S$ denote the polynomial ring in $2 n$ variables over a field. It is shown that the…

math.AC2025

Cohen-Macaulay squares of edge ideals

Sara Faridi, Takayuki Hibi

Let $G$ be a finite graph and $I (G)$ its edge ideal. We give a full description of the Stanley--Reisner complex of the polarization of $I (G)^{2}$ , naturally introducing the tools of…

math.CO2025

Vertex connectivity of chordal graphs

Tài Huy Hà, Takayuki Hibi

Let $G$ be a finite graph and $κ (G)$ the vertex connectivity of $G$ . A chordal graph $G$ is called chordal $^{*}$ if no vertex of $G$ is adjacent to all other vertices of $G$ . Using t…

math.AC2024

Gapfree graphs and powers of edge ideals with linear quotients

Nursel Erey, Sara Faridi, Tài Huy Hà +3

Let $I (G)$ be the edge ideal of a gapfree graph $G$ . An open conjecture of Nevo and Peeva states that $I (G)^{q}$ has linear resolution for $q ≫ 0$ . We present a promising approach t…

math.AC2024

Resolution and Betti numbers of Vertex cover ideals

Tài Huy Hà, Takayuki Hibi

The vertex cover ideal $J (G)$ of a finite graph $G$ is studied. We characterize when a Cohen--Macaulay vertex cover ideal $J (G)$ has a Scarf minimal free resolution. Furthermore, b…

math.CO2024★ 1 cited

A special class of pure $O$ -sequences

Tài Huy Hà, Takayuki Hibi, Fabrizio Zanello

The pure $O$ -sequences of the form $(1, a, a, \dots)$ are classified.

math.AC2024

Scarf complexes of graphs and their powers

Sara Faridi, Tài Huy Hà, Takayuki Hibi +1

Every multigraded free resolution of a monomial ideal I contains the Scarf multidegrees of I. We say I has a Scarf resolution if the Scarf multidegrees are sufficient to describe a…

Edge ideals of gapfree graphs with matching number 3

Depth of edge ideals and vertex connectivity of finite graphs

Symmetric and unimodal independence polynomials of trees

Independence polynomials of graphs

Pseudo-Gorenstein∗ Graphs

Binomial edge ideals of Cameron-Walker graphs

Cohen-Macaulay squares of edge ideals

Vertex connectivity of chordal graphs

Gapfree graphs and powers of edge ideals with linear quotients

Resolution and Betti numbers of Vertex cover ideals

A special class of pure O-sequences

Scarf complexes of graphs and their powers

Edge ideals of gapfree graphs with matching number $3$

Pseudo-Gorenstein $^{*}$ Graphs

A special class of pure $O$ -sequences