[GAP Forum] Cohomology computations, ExtensionRepresentatives: possible bug

[Bettina Eick]

Dear Vipul Naik, dear all,

I cannot reproduce the reproduce the reported bug:

gap> G := CyclicGroup(4);;
gap> A := TrivialGModule(G, GF(2));;
gap> A1 := AutomorphismGroup(G);;
gap> A2 := GL(1,2);;
gap> D := DirectProduct(A1,A2);;
gap> P := CompatiblePairs(G,A,D);;
gap> M := ExtensionRepresentatives(G,A,P);
[ <pc group of size 8 with 3 generators>,
   <pc group of size 8 with 3 generators> ]
gap> List(last, IdGroup);
[ [ 8, 2 ], [ 8, 1 ] ]
gap> Extensions(G,A);
[ <pc group of size 8 with 3 generators>,
   <pc group of size 8 with 3 generators> ]
gap> List(last, IdGroup);
[ [ 8, 2 ], [ 8, 1 ] ]

I am happy to discuss this further with Vipul Naik to sort out
what is going wrong here.

Best wishes,

Bettina