A characterization of binomial Macaulay dual generators for complete intersections
Kohsuke Shibata
TL;DR
The paper characterizes binomial Macaulay dual generators $F$ for which the Artinian algebra $R/\operatorname{Ann}_R(F)$ is a complete intersection, delivering necessary and sufficient conditions in terms of the binomial's support parameters $d_1,d_2$ and an integer $v$ defined via the Macaulay action. It provides explicit descriptions of $\operatorname{Ann}_R(F)$ in the CI cases and shows non-CI behavior when multiple nonzero $b_i$ occur, thereby completing the classification for binomial $F$. As an application, the authors prove that, in characteristic zero, any homogeneous binomial $F$ yielding a complete intersection algebra satisfies the strong Lefschetz property. These results extend earlier monomial and low-dimensional cases, offering a comprehensive understanding of binomial Macaulay dual generators in the complete-intersection regime and their Lefschetz behavior.
Abstract
We characterize a binomial such that the Artinian algebra whose Macaulay dual generator is the binomial is a complete intersection. As an application, we prove that the Artinian algebra with a binomial Macaulay dual generator has the strong Lefschetz property in characteristic 0 if the Artinian algebra is a complete intersection.
