3 papers
math.CO2025
A characterization of locally ordered ternary relations in terms of digraphs
Guillermo Gamboa Quintero, MartÃn Matamala, Juan Pablo Peña
In 1917, Huntington and Kline, followed by Huntington in 1924, studied systems of axioms for ternary relations aiming to capture the concepts of linear order (called betwenness) an…
math.CO2025
Minimum blocking sets for families of partitions
Guillermo Gamboa Quintero, Ida Kantor
A -partition of an -element set is a triple of pairwise disjoint nonempty subsets such that . We determine the minimum size of a set $\…
math.CO2024
Quasimetric spaces with few lines
Guillermo Gamboa Quintero, MartÃn Matamala, Juan Pablo Peña
Chen and Chvátal conjectured in 2008 that in any finite metric space either there is a line containing all the points - a universal line -, or the number of lines is at least the…