On the intersection of subgroups in free groups: Echelon subgroups are inert
نویسندگان
چکیده
منابع مشابه
Intersection of Subgroups in Free Groups and Homotopy Groups
We show that the intersection of three subgroups in a free group is related to the computation of the third homotopy group π3. This generalizes a result of Gutierrez-Ratcliffe who relate the intersection of two subgroups with the computation of π2. Let K be a twodimensional CW-complex with subcomplexes K1,K2,K3 such that K = K1 ∪ K2 ∪ K3 and K1 ∩ K2 ∩ K3 is the 1-skeleton K of K. We construct a...
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ژورنال
عنوان ژورنال: Groups - Complexity - Cryptology
سال: 2013
ISSN: 1867-1144,1869-6104
DOI: 10.1515/gcc-2013-0013