摘要
利用分数(g,f,n')-临界消去图的充要条件,借助最小反例构造的技巧,给出分数(g,f,n')-临界消去图的孤立韧度条件.指出在δ(G)≥bn'/a+(b+1)2/4a+b且I(G)>{b2+bn'-1/a,若b>a,b+n',若a=b.的条件下,G是分数(g,f,n')-临界消去图.
Determine the isolated toughness bound for fractional( g,f,n')-critical deleted graph in terms of the necessary and sufficient conditions of fractional( g,f,n')-critical deleted graph and the technology of minimal counterexample construction. It is presented that a graph is fractional( g,f,n')-critical deleted if δ( G) ≥bn'/a+( b +1)24a+ b and I( G) >{b2+ bn'-1/a,if b >a,b + n', if a =b.
引文
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