General interpolation problem for fat points
Determine the dimension of the linear system of degree-d forms in projective space that vanish to prescribed multiplicities at general points, for arbitrary numbers of points and multiplicities.
References
The problem is open in general.
— On the Hilbert series of ideals generated by general linear forms
(2608.22823 - Boij et al., 24 Aug 2026) in Section 2.1, subsection “The dimension of the linear system”