On subgraphs of Cartesian product graphs and S-primeness
In this paper we consider S-prime graphs, that is the graphs that cannot be represented as nontrivial subgraphs of nontrivial Cartesian products of graphs. Lamprey and Barnes characterized S-prime graphs via so-called basic S-prime graphs that form a subclass of all S-prime graphs. However, the stru...
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Published in | Discrete mathematics Vol. 282; no. 1; pp. 43 - 52 |
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Main Author | |
Format | Journal Article |
Language | English |
Published |
Amsterdam
Elsevier B.V
06.05.2004
Elsevier |
Subjects | |
Online Access | Get full text |
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Summary: | In this paper we consider S-prime graphs, that is the graphs that cannot be represented as nontrivial subgraphs of nontrivial Cartesian products of graphs. Lamprey and Barnes characterized S-prime graphs via so-called basic S-prime graphs that form a subclass of all S-prime graphs. However, the structure of basic S-prime graphs was not known very well. In this paper we prove several characterizations of basic S-prime graphs. In particular, the structural characterization of basic S-prime graphs of connectivity 2 enables us to present several infinite families of basic S-prime graphs. Furthermore, simple S-prime graphs are introduced that form a relatively small subclass of basic S-prime graphs, and it is shown that every basic S-prime graph can be obtained from a simple S-prime graph by a sequence of certain transformations called extensions. |
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ISSN: | 0012-365X 1872-681X |
DOI: | 10.1016/j.disc.2003.11.005 |