【摘 要】
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We prove that if G is a gap-free and chair-free simple graph,then the regularity of the edge ideal of G is no more than 3.If G is a gap-free and P4-free graph,t
【机 构】
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School of Mathematical Sciences, Shanghai Jiao Tong University Shanghai 200240, China
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We prove that if G is a gap-free and chair-free simple graph,then the regularity of the edge ideal of G is no more than 3.If G is a gap-free and P4-free graph,then it is a chair-free graph;furthermore,the complement of G is chordal,and thus the regularity of G is 2.
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