CLASSIFICATION OF BETTI DIAGRAMS OF VARIETIES OF ALMOST MINIMAL DEGREE

Title & Authors
CLASSIFICATION OF BETTI DIAGRAMS OF VARIETIES OF ALMOST MINIMAL DEGREE
Lee, Wan-Seok; Park, Eui-Sung;

Abstract
In this article we study the problem to determine all occurring Betti diagrams of varieties $\small{X{\subset}\mathbb{P}^r}$ of almost minimal degree, i.e. deg(X) = codim(X; $\small{\mathbb{P}^r}$)+2. We describe a realistic picture of how many different kind of Betti diagrams exist at all (Theorem 3.1). By means of the computer algebra system "SINGULAR", we obtain a complete list of all occurring Betti diagrams in the cases where codim$\small{(X,\mathbb{P}^r){\leq}8}$.
Keywords
minimal free resolution;Betti number;rational normal scroll;varieties of low degree;
Language
English
Cited by
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2.
On syzygies of divisors on rational normal scrolls, Mathematische Nachrichten, 2014, 287, 11-12, 1383
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