_LR := rec < recformat< F: GrpFP, AI: SeqEnum, G: GrpMat > |
      F := FreeGroup(2) >;
_LR`AI := [ [a^-1, b^-1] ] where a is (_LR`F).1 where b is (_LR`F).2;
//two constituents interchanged by _LR`AI[1][1]

_LR`G := sub<GL(6,Integers()) |
\[ -1,-1,1,1,-1,0,-1,-1,1,2,-1,1,0,-1,0,1,-1,0,-1,0,1,
1,-1,1,0,1,-1,-1,0,0,0,1,-1,-1,1,-1 ],
\[ 0,-1,0,1,0,0,0,-1,0,1,-1,0,1,-1,0,0,0,0,0,0,0,0,0,
-1,0,0,1,0,0,0,-1,-1,1,1,-1,1 ] >;

return _LR;
