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Large P4-free graphs with bounded degree

✍ Scribed by Myung S. Chung; Douglas B. West


Publisher
John Wiley and Sons
Year
1993
Tongue
English
Weight
424 KB
Volume
17
Category
Article
ISSN
0364-9024

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✦ Synopsis


Abstract

Let ex * (D; H) denote the maximum number of edges in a connected graph with maximum degree D and no induced subgraph isomorphic to H. We prove that this is finite only when H is a disjoint union of paths,m in which case we provide crude upper and lower bounds. When H is the four‐vertex path P~4~, we prove that the complete bipartite graph K~D,D~ is the unique extremal graph. Furthermore, if G is a connected P~4~‐free graph with maximum degree D and clique number Ο‰, then G has at most D^2^ βˆ’ D(Ο‰ βˆ’ 2)/2 edges. Β© 1993 John Wiley & Sons, Inc.


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