3 papers
math.CO2025
Separable convex optimization over indegree polytopes
Nóra A. Borsik, Péter Madarasi
We study egalitarian (acyclic) orientations of undirected graphs under indegree-based objectives, such as minimizing the -sum of indegrees for a strictly convex function ,…
math.CO2025
Vertex-ordering and arc-partitioning problems
Nóra A. Borsik, Péter Madarasi
We study vertex-ordering problems in loop-free digraphs subject to constraints on the left-going arcs, focusing on existence conditions and computational complexity. As an intrigui…
math.CO2025
Prefix-bounded matrices
Nóra A. Borsik, András Frank, Péter Madarasi +1
By unifying various earlier extensions of alternating sign matrices (ASMs), we introduce the notion of prefix-bounded matrices (PBMs). It is shown that the convex hull of these mat…