  
  [1X1 [33X[0;0YIntroduction[133X[101X
  
  [33X[0;0YThis  manual  describes  the  [5XIdRel[105X  package  for  [5XGAP[105X 4.7 for computing the
  identities  among  relators  of a group presentation using rewriting, logged
  rewriting, monoid polynomials, module polynomials and [22XY[122X-sequences.[133X
  
  [33X[0;0YThe  theoretical background for these computations is contained in Brown and
  Huebschumann  [BH82],  Brown  and Razak Salleh [BS99] and is surveyed in the
  first author's thesis [Hey99].[133X
  
  [33X[0;0Y[5XIdRel[105X  is  primarily  designed  for  the  computation  of  a  minimal set of
  generators  for  the  module  of identities among relators. It also contains
  functions  which compute logged rewrite systems for group presentations (and
  complete  them  where possible); functions for operations involving elements
  of monoid rings; and functions for operations with elements of right modules
  over  monoid  rings.  The  [22XY[122X-sequences  are  used  as  a  [13Xrewriting[113X  way  of
  representing  elements  of  a free crossed module (products of conjugates of
  group  relators  and  inverse  relators). The package is written entirely in
  [5XGAP[105X4, and requires no compilation.[133X
  
  [33X[0;0YThe  package  is  loaded  into [5XGAP[105X with the [10XLoadPackage[110X command, and on-line
  help is available in the usual way.[133X
  
  [4X[32X  Example  [32X[104X
    [4X[28X[128X[104X
    [4X[25Xgap>[125X [27XLoadPackage( "idrel" ); [127X[104X
    [4X[25Xgap>[125X [27X?idrel[127X[104X
    [4X[28X[128X[104X
  [4X[32X[104X
  
  [33X[0;0YA  pdf  version of the [5XIdRel[105X manual is available in the [11Xdoc[111X directory of the
  home  directory  of  [5XIdRel[105X.  The information parameter [10XInfoIdRel[110X has default
  value  [10X0[110X.  When  raised to a higher value, additional information is printed
  out.  [5XIdRel[105X was originally developed in 1999 using [5XGAP[105X3, partially supported
  by  a  University of Wales Research Assistantship for the first author, Anne
  Heyworth.[133X
  
  [33X[0;0YIf  you  use  [5XIdRel[105X to solve a problem then please send a short email to the
  second  author,  to  whom bug reports, suggestions and other comments should
  also  be  sent.  You  may  reference  the  package  by mentioning [HW03] and
  [Hey99].[133X
  
  [33X[0;0YThe current version is 2.34 for [5XGAP[105X 4.8, released on 20th October 2016.[133X
  
  [33X[0;0YThe  package  may  be obtained as a compressed tar file [11Xidrel-2.34.tar.gz[111X by
  ftp from one of the following sites:[133X
  
  [30X    [33X[0;6Yany                  [5XGAP[105X                 archive,                 e.g.
        [7Xhttp://www.gap-system.org/Packages/packages.html[107X;[133X
  
  [30X    [33X[0;6Ythe package GitHub repository: [7Xhttps://gap-packages.github.io/idrel[107X.[133X
  
