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A local structure theorem on 5-connected graphs

✍ Scribed by Kiyoshi Ando


Publisher
John Wiley and Sons
Year
2009
Tongue
English
Weight
281 KB
Volume
60
Category
Article
ISSN
0364-9024

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✦ Synopsis


Abstract

An edge of a 5‐connected graph is said to be contractible if the contraction of the edge results in a 5‐connected graph. Let x be a vertex of a 5‐connected graph. We prove that if there are no contractible edges whose distance from x is two or less, then either there are two triangles with x in common each of which has a distinct degree five vertex other than x, or there is a specified structure called a K~4~^−^‐configuration with center x. As a corollary, we show that if a 5‐connected graph on n vertices has no contractible edges, then it has 2__n__/5 vertices of degree 5. © 2008 Wiley Periodicals, Inc. J Graph Theory 60: 99–129, 2009


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