Very well-covered graphs by Betti splittings

被引:7
作者
Crupi, Marilena [1 ]
Ficarra, Antonino [1 ]
机构
[1] Univ Messina, Dept Math & Comp Sci Phys & Earth Sci, Viale Ferdinando Stagno Alcontres 31, I-98166 Messina, Italy
关键词
Complexes; Minimal resolutions; Betti splittings; Homological shift ideals; Vertex decomposability; Well-covered graphs; Very well-covered graphs; LOCAL COHOMOLOGY; MONOMIAL IDEALS; RINGS; RESOLUTIONS; BOUNDS;
D O I
10.1016/j.jalgebra.2023.03.033
中图分类号
O1 [数学];
学科分类号
0701 ; 070101 ;
摘要
A very well-covered graph is an unmixed graph without isolated vertices such that the height of its edge ideal is half of the number of vertices. We study these graphs by means of Betti splittings and mapping cone constructions. We show that the cover ideals of Cohen-Macaulay very well-covered graphs are splittable. As a consequence, we compute explicitly the minimal graded free resolution of the cover ideals of such a class of graphs and prove that these graphs have homological linear quotients. Finally, we conjecture the same is true for each power of the cover ideal of a Cohen-Macaulay very well- covered graph, and settle it in the bipartite case. (c) 2023 Elsevier Inc. All rights reserved.
引用
收藏
页码:76 / 108
页数:33
相关论文
共 35 条
[1]   LINEAR QUOTIENTS AND MULTIGRADED SHIFTS OF BOREL IDEALS [J].
Bayati, Shamila ;
Jahani, Iman ;
Taghipour, Nadiya .
BULLETIN OF THE AUSTRALIAN MATHEMATICAL SOCIETY, 2019, 100 (01) :48-57
[2]   Multigraded shifts of matroidal ideals [J].
Bayati, Shamila .
ARCHIV DER MATHEMATIK, 2018, 111 (03) :239-246
[3]   Betti splitting via componentwise linear ideals [J].
Bolognini, Davide .
JOURNAL OF ALGEBRA, 2016, 455 :1-13
[4]  
Bruns W., 1998, COHEN MACAULAY RINGS
[5]   COHEN-MACAULAY EDGE IDEAL WHOSE HEIGHT IS HALF OF THE NUMBER OF VERTICES [J].
Crupi, Marilena ;
Rinaldo, Giancarlo ;
Terai, Naoki .
NAGOYA MATHEMATICAL JOURNAL, 2011, 201 :117-131
[6]   Resolutions of Stanley-Reisner rings and Alexander duality [J].
Eagon, JA ;
Reiner, V .
JOURNAL OF PURE AND APPLIED ALGEBRA, 1998, 130 (03) :265-275
[7]  
Eisenbud D., 1995, COMMUTATIVE ALGEBRA
[8]   VERY WELL COVERED GRAPHS [J].
FAVARON, O .
DISCRETE MATHEMATICS, 1982, 42 (2-3) :177-187
[9]  
Ficarra A., 2022, HOMOLOGICALSHIFTSIDE
[10]   Dirac's Theorem and Multigraded Syzygies [J].
Ficarra, Antonino ;
Herzog, Jurgen .
MEDITERRANEAN JOURNAL OF MATHEMATICS, 2023, 20 (03)