Near subgroups of groups
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D.G. Hoffman; Sylvia Hobart; Ronald C. Mullin
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Article
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1995
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Elsevier Science
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English
โ 467 KB
A finite subset A of a group is a near subgroup if the number of ordered pairs (x, y) e A 2 with xy ~ A is at most I A [. We show here that if I A I >/5, then A is a near subgroup if and only if A w {g} is a subgroup for some group element g. We also classify the counterexamples if LAI~< 4.