Paulo Magalhães

activity

20242026

collaborators

5 papers

math.CO2026

Kriesell's conjecture for infinite graphs

Leandro Aurichi, Paulo Magalhães Júnior, Rodrigo Santos Monteiro

Let $G$ be a graph and $S \subseteq V (G)$ be a subset of vertices. An $S$ -Steiner tree $T$ of $G$ is a tree of $G$ which contains $S$ in its vertex set $V (T)$ . Kriesell conjectured…

math.CO2026

On some perfect matching conjectures in infinite, cubic, bridgeless graphs

Paulo Magalhães Júnior, Antonio Kelson Silva

The Berge-Fulkerson Conjecture states that every bridgeless cubic graph has six perfect matchings such that each edge belongs to exactly two of them. This conjecture has remained o…

math.GN2026

Ray and end spaces: characterizations and classification up to homeomorphism

Matheus Duzi, Gabriel Fernandes, Paulo Magalhães Júnior

We provide a combinatorial characterization for pairs of order-theoretic trees with homeomorphic ray spaces, answering an open problem proposed by Kurkofka ad Pitz. This solution i…

math.CO2025

On orientations preserving edge-connectivity in infinite graphs

Leandro Aurichi, Paulo Magalhães Júnior, Guilherme Eduardo Pinto

We prove that every 2k-edge-connected graph with countably many edge-ends admits a k-arc-connected orientation, extending the previous result by Assem, Koloschin and Pitz that also…

math.LO2024

Ray inflations of $ω_{1}$ -trees and ends of degree $ℵ_{1}$

Leandro Aurichi, Gabriel Fernandes, Paulo Magalhães Júnior

We prove the followings result for ray inflations of sparse graphs on $ω_{1}$ -trees. First, let $T$ and $S$ be pruned $ω_{1}$ -trees, let $G_{T}$ be a sparse $T$ -graph, and let $G_{S}$ be a…