Displaying similar documents to “Distinguishing number of countable homogeneous relational structures.”

Universality for and in Induced-Hereditary Graph Properties

Izak Broere, Johannes Heidema (2013)

Discussiones Mathematicae Graph Theory

Similarity:

The well-known Rado graph R is universal in the set of all countable graphs I, since every countable graph is an induced subgraph of R. We study universality in I and, using R, show the existence of 2 א0 pairwise non-isomorphic graphs which are universal in I and denumerably many other universal graphs in I with prescribed attributes. Then we contrast universality for and universality in induced-hereditary properties of graphs and show that the overwhelming majority of induced-hereditary...

Universality in Graph Properties with Degree Restrictions

Izak Broere, Johannes Heidema, Peter Mihók (2013)

Discussiones Mathematicae Graph Theory

Similarity:

Rado constructed a (simple) denumerable graph R with the positive integers as vertex set with the following edges: For given m and n with m < n, m is adjacent to n if n has a 1 in the m’th position of its binary expansion. It is well known that R is a universal graph in the set [...] of all countable graphs (since every graph in [...] is isomorphic to an induced subgraph of R). A brief overview of known universality results for some induced-hereditary subsets of [...] is provided....

One-Three Join: A Graph Operation and Its Consequences

M.A. Shalu, S. Devi Yamini (2017)

Discussiones Mathematicae Graph Theory

Similarity:

In this paper, we introduce a graph operation, namely one-three join. We show that the graph G admits a one-three join if and only if either G is one of the basic graphs (bipartite, complement of bipartite, split graph) or G admits a constrained homogeneous set or a bipartite-join or a join. Next, we define ℳH as the class of all graphs generated from the induced subgraphs of an odd hole-free graph H that contains an odd anti-hole as an induced subgraph by using one-three join and co-join...