GAP 4.8.9 installation with standard packages -- copy to your CoCalc project to get it
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##
#W sl25pc.g XMOD example files Chris Wensley
##
#Y Copyright (C) 2001-2016, Chris Wensley et al,
#Y School of Computer Science, Bangor University, U.K.
##
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SetInfoLevel( InfoXMod, 2 );
Print("\nXMod test file sl25pc.g (version 10/11/15) :-\n\n");
sl25pc := SpecialLinearGroup(2,5);
SetName( sl25pc, "sl25-pc" );
gensl25pc := GeneratorsOfGroup( sl25pc );
Print( "sl25pc has generators: ", gensl25pc, "\n" );
ccsl := ConjugacyClassesSubgroups( sl25pc );
repssl := List( ccsl, c -> Representative(c) );
Print( "conj. classes: ", List( repssl, r -> Size(r) ), "\n" );
Print( List( repssl, r -> StructureDescription(r) ), "\n" );
gl25pc := GeneralLinearGroup(2,5);
SetName( gl25pc, "gl25-pc" );
gengl25pc := GeneratorsOfGroup( gl25pc );
Print( "gl25pc has generators: ", gengl25pc, "\n" );
isofp := IsomorphismFpGroup( gl25pc );
imisofp := Image( isofp );
isofpinfo := IsomorphismFpInfo( gl25pc );
fgensim := FreeGeneratorsOfFpGroup( imisofp );
gensim := GeneratorsOfGroup( imisofp );
ok := fgensim=gensim;
Print( "free gens = gens? ", ok, "\n" );
## ok := ok[3];
ccgl := ConjugacyClassesSubgroups( gl25pc );
repsgl := List( ccgl, c -> Representative(c) );
Print( "conj. classes: ", List( repsgl, r -> Size(r) ), "\n" );
Print( List( repsgl, r -> StructureDescription(r) ), "\n" );
lengl := Length( repsgl );
sl25c2pc := repsgl[lengl-1];
SetName( sl25c2pc, "sl25.c2-pc" );
gensl25c2pc := GeneratorsOfGroup( sl25c2pc );
inc25pc := InclusionMappingGroups( gl25pc, sl25c2pc );
Print( "inc25pc = ", inc25pc, "\n" );
X25pc := XModByNormalSubgroup( sl25c2pc, sl25pc );
indX25pc := InducedXMod( X25pc, inc25pc );
Display( indX25pc );
h25pc := Source( indX25pc );
Print( "h25pc = ", StructureDescription( h25pc ), "\n" );