Download PDF - Convex universal fixers
ArticleOriginal scientific text
Title
Convex universal fixers
Authors 1, 2
Affiliations
- Gdańsk University of Technology, Narutowicza 11/12, 80-233 Gdańsk, Poland
- Departamento de Matematicas, Facultad de Ciencias, UNAM, Mexico
Abstract
In [1] Burger and Mynhardt introduced the idea of universal fixers. Let G = (V, E) be a graph with n vertices and G' a copy of G. For a bijective function π: V(G) → V(G'), define the prism πG of G as follows: V(πG) = V(G) ∪ V(G') and , where . Let γ(G) be the domination number of G. If γ(πG) = γ(G) for any bijective function π, then G is called a universal fixer. In [9] it is conjectured that the only universal fixers are the edgeless graphs K̅ₙ. In this work we generalize the concept of universal fixers to the convex universal fixers. In the second section we give a characterization for convex universal fixers (Theorem 6) and finally, we give an in infinite family of convex universal fixers for an arbitrary natural number n ≥ 10.
Keywords
convex sets, dominating sets, universal fixers
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