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NEIGHBOURHOOD AND THE EXISTENCE OF FRACTIONAL k-FACTORS OF GRAPHS

Published online by Cambridge University Press:  13 January 2010

SIZHONG ZHOU*
Affiliation:
School of Mathematics and Physics, Jiangsu University of Science and Technology, Mengxi Road 2, Zhenjiang, Jiangsu 212003, PR China (email: [email protected])
BINGYUAN PU
Affiliation:
Department of Fundamental Course, Chengdu Textile College, Chengdu, Sichuan 611731, PR China
YANG XU
Affiliation:
Department of Mathematics, Qingdao Agricultural University, Qingdao, Shandong 266109, PR China (email: [email protected])
*
For correspondence; e-mail: [email protected]
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Abstract

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Let G be a graph, and k a positive integer. Let h:E(G)→[0,1] be a function. If ∑ exh(e)=k holds for each xV (G), then we call G[Fh] a fractional k-factor of G with indicator function h where Fh={eE(G)∣h(e)>0}. In this paper we use neighbourhoods to obtain a new sufficient condition for a graph to have a fractional k-factor. Furthermore, this result is shown to be best possible in some sense.

Type
Research Article
Copyright
Copyright © Australian Mathematical Publishing Association Inc. 2010

Footnotes

This research was sponsored by Qing Lan Project of Jiangsu Province and was supported by Jiangsu Provincial Educational Department (07KJD110048) and Sichuan Provincial Educational Department (08zb068).

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