On a theorem of F. S. Macaulay on colon ideals.
On curves on rational normal scrolls.
On finite algebras projectively represented by graded complete intersections.
On Hilbert polynomial of certain determinantal ideals.
On Landsberg's criterion for complete intersections.
On linked surfaces in .
On the homology of some special complexes. (Sobre la homología de algunos complejos especiales.)
On the Jacobian ideal of the binary discriminant.
Let Δ denote the discriminant of the generic binary d-ic. We show that for d ≥ 3, the Jacobian ideal of Δ is perfect of height 2. Moreover we describe its SL2-equivariant minimal resolution and the associated differential equations satisfied by Δ. A similar result is proved for the resultant of two forms of orders d, e whenever d ≥ e-1. If Φn denotes the locus of binary forms with total root multiplicity ≥ d-n, then we show that the ideal of Φn is also perfect, and we construct a covariant which...
On the structure of certain normal ideals
On the upper semicontinuity intersection defect.