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.
Subgroups of graph groups
โ Scribed by Carl Droms
- Publisher
- Elsevier Science
- Year
- 1987
- Tongue
- English
- Weight
- 227 KB
- Volume
- 110
- Category
- Article
- ISSN
- 0021-8693
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