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WLP for (a, b)-geproci sets

Determine for which integers d and which (a, b)-geproci sets X ⊂ P^3 the Artinian algebra R/A_{X,d}, where A_{X,d} is the ideal generated by the d-th powers of the linear forms dual to the points of X, has the Weak Lefschetz Property.

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Background

A set X ⊂ P3 is (a, b)-geproci if its general projection to P2 is a complete intersection of type (a, b). Grids are special examples of geproci sets that lie on a smooth quadric, enabling precise control of projections and the Hilbert functions of powers of complete intersection ideals.

The authors provide general cokernel-dimension formulas for multiplications by a general linear form in the geproci setting (Lemma 4.1), but beyond grids the structure is more delicate because most geproci sets do not lie on a quadric. This question seeks a characterization of when R/A_{X,d} has WLP across the broader geproci class.

References

Question 8.6. Let X be an (a, b)-geproci set. When does R/Ax,a have the WLP?

On the Weak Lefschetz Property for certain ideals generated by powers of linear forms (2406.09571 - Favacchio et al., 13 Jun 2024) in Section 8, Question 8.6