2 papers
math.CO2026
Modularity, Extensions and Connectivity in Infinite Matroids
Mattias Ehatamm, Peter Nelson, Fernanda Rivera Omana
We generalize the well-studied notion of a modular pair of a finite matroid to arbitrary families of sets in infinite matroids, and use it to develop the theory of infinite matroid…
math.CO2023
On the density of matroids omitting a complete-graphic minor
Peter Nelson, Sergey Norin, Fernanda Rivera Omana
We show that, if is a simple rank- matroid with no -point line minor and no minor isomorphic to the cycle matroid of a -vertex complete graph, then the ratio $|M| /…