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Constructing trees in graphs with no K2,s

✍ Scribed by Suman Balasubramanian; Edward Dobson


Book ID
102345562
Publisher
John Wiley and Sons
Year
2007
Tongue
English
Weight
150 KB
Volume
56
Category
Article
ISSN
0364-9024

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✦ Synopsis


Abstract

Let s β‰₯ 2 be an integer and k > 12(sβ€‰βˆ’β€‰1) an integer. We give a necessary and sufficient condition for a graph G containing no K~2,s~ with $\delta(G)\ge{k}/2$ and $\Delta(G)\ge k$ to contain every tree T of order k + 1. We then show that every graph G with no K~2,s~ and average degree greater than kβ€‰βˆ’β€‰1 satisfies this condition, improving a result of Haxell, and verifying a special case of the ErdΕ‘sβ€”SΓ³s conjecture, which states that every graph of average degree greater than kβ€‰βˆ’β€‰1 contains every tree of order k + 1. Β© 2007 Wiley Periodicals, Inc. J Graph Theory 56: 301–310, 2007


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