Induced matching, ordered matching and Castelnuovo-Mumford regularity of bipartite graphs
Algebraic Combinatorics, Volume 9 (2026) no. 1, pp. 41-50

Let $G$ be a finite simple graph and let $\operatorname{ind-match}(G)$ and $\operatorname{ord-match}(G)$ denote the induced matching number and the ordered matching number of $G$, respectively. We characterize all bipartite graphs $G$ with $\operatorname{ind-match}(G)=\operatorname{ord-match}(G)$. We establish the Castelnuovo-Mumford regularity of powers of edge ideals and depth of powers of cover ideals for such graphs.

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DOI: 10.5802/alco.461
Classification: 10X99, 14A12, 11L05
Keywords: Induced matching, ordered matching, Castelnuovo-Mumford regularity, depth, edge ideal, cover ideal

Jayanthan, A. V.  1 ; Seyed Fakhari, Seyed Amin  2 ; Swanson, Irena  3 ; Yassemi, Siamak  4

1 Department of Mathematics, I.I.T. Madras, Chennai, Tamil Nadu 600036, India
2 Departamento de Matemáticas, Universidad de los Andes, Bogotá, Colombia
3 Department of Mathematics, Purdue University, West Lafayette, IN 47907, USA
4 Department of Mathematics, Purdue University, Indianapolis, IN 46202, USA
License: CC-BY 4.0
Copyrights: The authors retain unrestricted copyrights and publishing rights
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Jayanthan, A. V.; Seyed Fakhari, Seyed Amin; Swanson, Irena; Yassemi, Siamak. Induced matching, ordered matching and Castelnuovo-Mumford regularity of bipartite graphs. Algebraic Combinatorics, Volume 9 (2026) no. 1, pp. 41-50. doi: 10.5802/alco.461

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