gens:=[
    Matrix(GF(3),3,3,[1, 2, 0, 0, 2, 0, 0, 2, 1 ]),

    Matrix(GF(3),3,3,[2, 0, 0, 2, 1, 0, 2, 0, 1 ]),

    Matrix(GF(3),3,3,[1, 2, 0, 0, 2, 0, 0, 2, 1 ]),

    Matrix(GF(3),3,3,[1, 0, 0, 0, 1, 0, 0, 0, 1 ]),

    Matrix(GF(3),3,3,[2, 0, 1, 2, 1, 0, 2, 0, 0 ]),

    Matrix(GF(3),3,3,[0, 2, 1, 0, 2, 0, 1, 2, 0 ])
];

NHC:=PermutationGroup<22|(2, 17)(4, 16)(6, 13)(7, 14)(8, 9)(10, 11)(15, 18)(19, 20),(1, 6)(2, 14)(3, 10)(4, 7)(9, 12)(15, 18)(16, 17)(20, 21), (2, 17)(4, 16)(6, 13)(7, 14)(8, 9)(10, 11)(15, 18)(19, 20), (1, 16, 4)(2, 14, 13)(3, 11, 10)(5, 15, 18)(6, 7, 17)(8, 12, 9), (1, 15, 17)(2, 14, 13)(4, 5, 7)(6, 16, 18)(8, 9, 12)(20, 21, 22), (1, 5)(2, 7)(4, 18)(6, 13)(14, 17)(15, 16)(19, 20)(21, 22)>;




V21:=GModule(NHC,gens);


print("Green correspondent V21 of the simple M22-module 
D21 in NHC (normalizer of vertex C in M22) over GF(3)");