Some polynomial classes for the acyclic orientation with parity constraint problem

This paper identifies three necessary conditions for the existence of acyclic T-odd orientations, defines and characterizes polynomial graph classes where these conditions are sufficient, and provides constructive polynomial-time algorithms to build such orientations for these classes and their Cartesian products.

Sylvain Gravier (IF, SFR MAM), Matthieu Petiteau (IF, SFR MAM), Isabelle Sivignon (GIPSA-GAIA, SFR MAM)Wed, 11 Ma🔢 math

On the Multi-Commodity Flow with convex objective function: Column-Generation approaches

This paper proposes a column-generation-based algorithmic framework to efficiently solve both splittable and unsplittable variants of the capacitated Multi-Commodity Flow problem with convex, potentially non-differentiable, link cost functions, offering a robust optimization approach for managing traffic in telecommunication networks.

Guillaume Beraud-Sudreau, Lucas Létocart, Youcef Magnouche, Sébastien MartinWed, 11 Ma💻 cs

A note on approximating the average degree of bounded arboricity graphs

This paper presents a simplified and fully analyzed sublinear-time algorithm that achieves a (1+ε)(1+\varepsilon)-approximation of the average degree in bounded arboricity graphs using O(ε2α/d)O(\varepsilon^{-2}\alpha/d) queries, thereby recovering logarithmic factors lost in previous work and offering a modified version with O(ε2n/d)O(\varepsilon^{-2}\sqrt{n/d}) query complexity.

Talya Eden, C. SeshadhriTue, 10 Ma💻 cs

When Many Trees Go to War: On Sets of Phylogenetic Trees With Almost No Common Structure

This paper establishes that for a set of tt phylogenetic trees with nn leaves, if tt is sufficiently small (specifically to(lgn)t \in o(\sqrt{\lg n})), the trees can be constructed to have virtually no common structure, thereby forcing any network displaying them to require nearly the maximum possible number of reticulations, (t1)no(n)(t-1)n - o(n).

Mathias Weller, Norbert ZehTue, 10 Ma🔢 math