论文信息 - The Asphericity and Freiheitssatz for Certain Lot-Presentations of Groups

The Asphericity and Freiheitssatz for Certain Lot-Presentations of Groups

Let U be a word in letters , m >2, and a group G be given by presentation G= . It is proven that this presentation is aspherical provided the word U does not have the form U2 U1, where U1 is a word in letters and U2 is a word in letters . It is also proven that the (images of) x1,…, xm-1 freely generate a free subgroup of G if and only if the word U does not have the foregoing form U2 U1.

Sergei V. Ivanov | A. A. Klyachko | S. Ivanov | A. Klyachko

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