Algebraic properties of product of graphs
arXiv:1101.0515
Abstract
Let and be two simple graphs and let denotes the graph theoretical product of by . In this paper we provide some results on graded Betti numbers, Castelnuovo-Mumford regularity, projective dimension, -vector, and Hilbert series of in terms of that information of and . To do this, we will provide explicit formulae to compute graded Betti numbers, -vector, and Hilbert series of disjoint union of complexes. Also we will prove that the family of graphs whose regularity equal the maximum number of pairwise -disjoint edges, is closed under product of graphs.
18 pages