On the Hilbert functions of sets of points in P^1 x P^1 x P^1

Abstract

Let H_X be the trigraded Hilbert function of a set X of reduced points in P^1 x P^1 x P^1. We show how to extract some geometric information about X from H_X. This note generalizes a similar result of Giuffrida, Maggioni, and Ragusa about sets of points in P^1 x P^1.

10 pages; corrected version (minor typos and extra detail added); to appear in Math. Proc. Cambridge Philos. Soc