Hilbert functions of double point schemes in P^2

Abstract

We study the question of whether there is a minimum Hilbert functions for double point schemes whose support is $s$ points with the generic Hilbert functions. Previous work shows that the question has an affirmative answer for $s \le 9$ and for $s$ equal to a binomial coefficient number. In this paper, we give evidence in the case when $s$ equals to a binomial coefficient number plus 1, and give an affirmative answer to the question when $s = 11$.