539 research outputs found
Matchings, coverings, and Castelnuovo-Mumford regularity
We show that the co-chordal cover number of a graph G gives an upper bound
for the Castelnuovo-Mumford regularity of the associated edge ideal. Several
known combinatorial upper bounds of regularity for edge ideals are then easy
consequences of covering results from graph theory, and we derive new upper
bounds by looking at additional covering results.Comment: 12 pages; v4 has minor changes for publicatio
Regularity of Edge Ideals and Their Powers
We survey recent studies on the Castelnuovo-Mumford regularity of edge ideals
of graphs and their powers. Our focus is on bounds and exact values of and the asymptotic linear function , for in terms of combinatorial data of the given graph Comment: 31 pages, 15 figure
The square of the line graph and path ideals
For path ideals of the square of the line graph we compute the Krull dimension, we characterize the linear resolution property in combinatorial terms. We bound the Castelnuovo-Mumford regularity and the projective dimension in terms of the corresponding invariants of two sub-hypergraph. We present some open questions
- âŠ