3 papers
math.AT2018
A local Jordan-Brouwer separation theorem
Alexander Lemmens
We intoduce a local version of the Jordan-Brouwer separation theorem and deduce some global statements, some of which may follow from known results, but the technique is new.
math.AG2018
On syzygies of Segre embeddings of
Alexander Lemmens
We construct a nonminimal graded free resolution of Segre embeddings of , although we don't compute all maps. We use this to prove an explicit formula for certain no…
math.CO2017
Minimal polygons with fixed lattice width
Filip Cools, Alexander Lemmens
We classify the unimodular equivalence classes of inclusion-minimal polygons with a certain fixed lattice width. As a corollary, we find a sharp upper bound on the number of lattic…