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Free crossed resolutions of groups and presentations of modules of identities among relations

Ronald Brown·A. Razak Salleh
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Abstract

We give formulae for a module presentation of the module of identities among relations for a presentation of a group, in terms of information on 0- and 1-combings of the Cayley graph. This is seen as a special case of extending a partial free crossed resolution of a group given a partial contracting homotopy of its universal cover.

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Ronald Brown, A. Razak Salleh. 1998-12-22. Free crossed resolutions of groups and presentations of modules of identities among relations. https://arxiv.org/abs/math/9812132

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