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

نویسندگان

  • RONALD BROWN
  • ABDUL RAZAK SALLEH
چکیده

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 0and 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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تاریخ انتشار 2008