On graphs with isomorphic, non-isomorphic and connected -neighbourhoods
Zdeněk Ryjáček (1987)
Časopis pro pěstování matematiky
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Displaying similar documents to “Locally graphs.”
On graphs with isomorphic, non-isomorphic and connected -neighbourhoods
Randomly complete -partite graphs
Yousef Alavi, Don R. Lick, Song Lin Tian (1989)
Mathematica Slovaca
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The perfection and recognition of bull-reducible Berge graphs
Hazel Everett, Celina M. H. de Figueiredo, Sulamita Klein, Bruce Reed (2005)
RAIRO - Theoretical Informatics and Applications - Informatique Théorique et Applications
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The recently announced Strong Perfect Graph Theorem states that the class of perfect graphs coincides with the class of graphs containing no induced odd cycle of length at least 5 or the complement of such a cycle. A graph in this second class is called Berge. A bull is a graph with five vertices and five edges . A graph is bull-reducible if no vertex is in two bulls. In this paper we give a simple proof that every bull-reducible Berge graph is perfect. Although this result follows...
Graphs with nonisomorphic vertex neighbourhoods of the first and second types
Zdeněk Ryjáček (1987)
Časopis pro pěstování matematiky
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Gallai and anti-Gallai graphs of a graph
S. Aparna Lakshmanan, S. B. Rao, A. Vijayakumar (2007)
Mathematica Bohemica
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The paper deals with graph operators—the Gallai graphs and the anti-Gallai graphs. We prove the existence of a finite family of forbidden subgraphs for the Gallai graphs and the anti-Gallai graphs to be -free for any finite graph . The case of complement reducible graphs—cographs is discussed in detail. Some relations between the chromatic number, the radius and the diameter of a graph and its Gallai and anti-Gallai graphs are also obtained.