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A SUFFICIENT CONDITION FOR A GRAPH TO BE A FRACTIONAL (f, n)-CRITICAL GRAPH

Published online by Cambridge University Press:  29 March 2010

SIZHONG ZHOU*
Affiliation:
School of Mathematics and Physics, Jiangsu University of Science and Technology, Mengxi Road 2, Zhenjiang, Jiangsu 212003, People's Republic of China e-mail: zsz_cumt@163.com
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Abstract

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Let a, b and n be non-negative integers such that 1 ≤ ab, and let G be a graph of order p with and f be an integer-valued function defined on V(G) such that af(x) ≤ b for all xV(G). Let h: E(G) → [0, 1] be a function. If ∑exh(e) = f(x) holds for any xV(G), then we call G[Fh] a fractional f-factor of G with indicator function h, where Fh = {eE(G): h(e) > 0}. A graph G is called a fractional (f, n)-critical graph if after deleting any n vertices of G the remaining graph of G has a fractional f-factor. In this paper, it is proved that G is a fractional (f, n)-critical graph if for every non-empty independent subset X of V(G), and . Furthermore, it is shown that the result in this paper is best possible in some sense.

Keywords

Type
Research Article
Copyright
Copyright © Glasgow Mathematical Journal Trust 2010

References

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