✦ LIBER ✦

Short proofs for two theorems of Chien, Hell and Zhu

✍ Scribed by Tracy Holt; Yared Nigussie

Publisher: John Wiley and Sons
Year: 2010
Tongue: English
Weight: 99 KB
Volume: 66
Category: Article
ISSN: 0364-9024
DOI: 10.1002/jgt.20515

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✦ Synopsis

In (J Graph Theory 33 (2000)

, 14-24), Hell and Zhu proved that if a series-parallel graph G has girth at least 2 (3k -1) / 2 , then c (G) ≤ 4k / (2k -1). In (J Graph Theory 33 (2000), [185][186][187][188][189][190][191][192][193][194][195][196][197][198], Chien and Zhu proved that the girth condition given in (J Graph Theory 33 (2000), 14-24) is sharp. Short proofs of both results are given in this note.

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