ISSN 1234-3099 (print version)

ISSN 2083-5892 (electronic version)

Discussiones Mathematicae Graph Theory

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Discussiones Mathematicae Graph Theory


Discussiones Mathematicae Graph Theory 23(1) (2003) 141-158
DOI: 10.7151/dmgt.1191


Ralph Faudree

Department of Mathematical Science
University of Memphis
Memphis, TN 38152, USA

Annette Schelten and Ingo Schiermeyer

Fakultät für Mathematik und Informatik
Technische Universität Bergakademie Freiberg
09596 Freiberg, Germany


Bondy and Erdős [2] have conjectured that the Ramsey number for three cycles Ck of odd length has value r(Ck,Ck,Ck)=4k−3. We give a proof that r(C7,C7,C7)=25 without using any computer support.

Keywords: Ramsey numbers, extremal graphs.

2000 Mathematics Subject Classification: 05C55, 05C35.


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Received 30 July 2001
Revised 18 January 2002