73.120 Norrie crossed module

Norrie( X )

This crossed module has the range of X as source and the automorphism permutation group of X as range.

    gap> NXSC := Norrie( XSC );
    Crossed module Norrie[c3->s3]
    gap> XModPrint( NXSC );

    Crossed module Norrie[c3->s3] :- 
    : Source group has parent ( c3^2

Xc2 ) and has generators:
      [ (4,5,6), (2,3)(5,6) ]
    : Range group has parent ( PermAut(c3)xPermAut(s3) ) and has
        generators: [ (5,6,7), (1,2)(3,4)(6,7) ]
    : Boundary homomorphism maps source generators to:
      [ (5,7,6), (1,2)(3,4)(6,7) ]
    : Action homomorphism maps range generators to automorphisms:
      (5,6,7) --> { source gens --> [ (4,5,6), (2,3)(4,5) ] }
      (1,2)(3,4)(6,7) --> { source gens --> [ (4,6,5), (2,3)(5,6) ] }
      These 2 automorphisms generate the group of automorphisms.  

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