4 papers
math.CO2025
A short proof of an upper bound on the growth constant of polyiamonds
Vuong Bui
We provide a short and elementary proof that the growth constant of polyiamonds is at most for the unique real root of the equation . This coincidenta…
math.CO2025
A characterization of the Carathéodory number for -convexity
Vuong Bui
We show that the Carathéodory number for -convexity is the maximum of two parameters: the Helly number for -convexity and the cone number of . The cone number in this arti…
math.CO2024
Bounding Klarner's constant from above using a simple recurrence
Vuong Bui
Klarner and Rivest showed that the growth of the number of polyominoes, also known as Klarner's constant, is at most by viewing polyominoes as a sequence of twig…
math.CO2021
A characterization of strongly monotypic polytopes
Vuong Bui
We characterize all the strongly monotypic polytopes. Hadwiger's conjecture for this class of polytopes is deduced from the characterization.