ArticleOriginal scientific text

Title

Convex universal fixers

Authors 1, 2

Affiliations

  1. Gdańsk University of Technology, Narutowicza 11/12, 80-233 Gdańsk, Poland
  2. 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 E(πG)=E(G)E(G)Mπ, where Mπ={uπ(u)uV(G)}. 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

Bibliography

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Pages:
807-812
Main language of publication
English
Received
2011-08-25
Accepted
2011-11-14
Published
2012
Exact and natural sciences