2019/08/28 by Banerjee, Arindam, Das, Priya, Selvaraja, S.
#05C70 #05E45 #Combinatorics (math.CO) #Commutative Algebra (math.AC) #FOS: Mathematics #Primary: 13D02
paper · doi:10.48550/arxiv.1908.10573
Let I and J be edge ideals in a polynomial ring R = \mathbbK[x1,…,xn] with I ⊆ J. In this paper, we obtain a general upper and lower bound for the Castelnuovo-Mumford regularity of IJ in terms of certain invariants associated with I and J. Using these results, we explicitly compute the regularity of IJ for several classes of edge ideals. Let J1,…,Jd be edge ideals in a polynomial ring R with J1 ⊆ ⋯ ⊆ Jd. Finally, we compute the precise expression for the regularity of J1 J2⋯ Jd when d ∈ \3,4\ and Jd is the edge ideal of complete graph.