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The maximum valency of regular graphs with given order and odd girth

✍ Scribed by Guo-Hui Zhang


Publisher
John Wiley and Sons
Year
1992
Tongue
English
Weight
294 KB
Volume
16
Category
Article
ISSN
0364-9024

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✦ Synopsis


Abstract

The odd girth of a graph G is the length of a shortest odd cycle in G. Let d(n, g) denote the largest k such that there exists a k‐regular graph of order n and odd girth g. It is shown that d____n, g β‰₯ 2|n/gβ‰₯ if n β‰₯ 2__g__. As a consequence, we prove a conjecture of Pullman and Wormald, which says that there exists a 2__j__‐regular graph of order n and odd girth g if and only if n β‰₯ gj, where g β‰₯ 5 is odd and j β‰₯ 2. A different variation of the problem is also discussed.


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