Cohen-Macaulayness of tower sets and Betti Weak Lefschetz Property

Abstract

We deal with the Cohen-Macaulay property for monomial squarefree ideals. We characterize the Cohen-Macaulay squarefree monomial ideals of codimension two just looking at their minimal prime ideals. We introduce the notion of tower sets and other configurations which preserve the Cohen-Macaulayness. We study the Hilbert function and the graded Betti numbers for generic linear quotients of Artinian standard graded algebras, especially in the case of Weak Lefschetz algebras. Moreover, we investigate a particular property of Weak Lefschetz algebras, the Betti Weak Lefschetz Property, which makes possible to completely determinate the graded Betti numbers of a generic linear quotient of such algebras.