ON THE EXTREMAL BETTI NUMBERS OF SQUAREFREE MONOMIAL IDEALS

Abstract

Let $K$ be a field and $S=K[x_1,\dots,x_n]$ be a polynomial ring over $K$. We discuss the behaviour of the extremal Betti numbers of the class of squarefree strongly stable ideals. More precisely, we give a numerical characterization of the possible extremal Betti numbers (values as well as positions) of such a class of squarefree monomial ideals.

Keywords

• Graded ideal
• squarefree monomial ideal
• minimal graded resolution

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