gap> uu:=(1,3)(2,4);ff:=(1,8)(4,5);dd:=(5,7)(6,8); (1,3)(2,4) (1,8)(4,5) (5,7)(6,8) gap> bb:=(3,6)(2,7);rr:=(2,5)(1,6);ll:=(4,7)(3,8); (2,7)(3,6) (1,6)(2,5) (3,8)(4,7) gap> H:=Group(uu,ff,rr,dd,bb,ll); Group( (1,3)(2,4), (1,8)(4,5), (1,6)(2,5), (5,7)(6,8), (2,7)(3,6), (3,8) (4,7) ) gap> H1:=Stabilizer(H,1); Subgroup( Group( (1,3)(2,4), (1,8)(4,5), (1,6)(2,5), (5,7)(6,8), (2,7)(3,6), (3,8)(4,7) ), [ (5,7)(6,8), (2,7)(3,6), (3,8)(4,7) ] ) gap> Size(H1); 24 gap> L1:=Lattice(H1); LatticeSubgroups( Subgroup( Group( (1,3)(2,4), (1,8)(4,5), (1,6)(2,5), (5,7) (6,8), (2,7)(3,6), (3,8)(4,7) ), [ (5,7)(6,8), (2,7)(3,6), (3,8)(4,7) ] ) ) gap> N1:=NormalSubgroups(H1); [ Subgroup( Group( (1,3)(2,4), (1,8)(4,5), (1,6)(2,5), (5,7)(6,8), (2,7) (3,6), (3,8)(4,7) ), [ ] ), Subgroup( Group( (1,3)(2,4), (1,8)(4,5), (1,6)(2,5), (5,7)(6,8), (2,7)(3,6), (3,8)(4,7) ), [ (2,4)(5,7), (2,5)(4,7) ] ), Subgroup( Group( (1,3)(2,4), (1,8)(4,5), (1,6)(2,5), (5,7)(6,8), (2,7)(3,6), (3,8)(4,7) ), [ (3,6,8)(4,5,7), (2,4,5)(3,8,6) ] ), Subgroup( Group( (1,3)(2,4), (1,8) (4,5), (1,6)(2,5), (5,7)(6,8), (2,7)(3,6), (3,8)(4,7) ), [ (5,7)(6,8), (2,5)(3,8), (3,6)(4,5) ] ) ] gap> Size(N1[1]); 1 gap> Size(N1[2]); 4 gap> Size(N1[3]); 12 gap> Size(N1[4]); 24 gap> Size(N1[5]); Error, List Element: [5] must have a value gap> H2:=Stabilizer(H,2); Subgroup( Group( (1,3)(2,4), (1,8)(4,5), (1,6)(2,5), (5,7)(6,8), (2,7)(3,6), (3,8)(4,7) ), [ (5,7)(6,8), (3,8)(4,7), (1,6,8,3)(4,5) ] ) gap> Intersection(H1,H2); Subgroup( Group( (1,3)(2,4), (1,8)(4,5), (1,6)(2,5), (5,7)(6,8), (2,7)(3,6), (3,8)(4,7) ), [ (5,7)(6,8), (3,8)(4,7) ] ) gap> H12:=Intersection(H1,H2); Subgroup( Group( (1,3)(2,4), (1,8)(4,5), (1,6)(2,5), (5,7)(6,8), (2,7)(3,6), (3,8)(4,7) ), [ (5,7)(6,8), (3,8)(4,7) ] ) gap> Size(H12); 6 gap> IsConjugateSubgroup(H1,H2); Error, Variable: 'IsConjugateSubgroup' must have a value gap> ConjugateSubgroup(H1,H2); Error, must be an element of the parent group of in ConjugateSubgroup( H1, H2 ) called from main loop brk> quit; gap> Size(H2); 24 gap> H3:=Stabilizer(H,3); Subgroup( Group( (1,3)(2,4), (1,8)(4,5), (1,6)(2,5), (5,7)(6,8), (2,7)(3,6), (3,8)(4,7) ), [ (5,7)(6,8), (1,8)(2,7), (1,6,8)(2,4,5) ] ) gap> H123:=Intersection(H12,H3); Subgroup( Group( (1,3)(2,4), (1,8)(4,5), (1,6)(2,5), (5,7)(6,8), (2,7)(3,6), (3,8)(4,7) ), [ (5,7)(6,8) ] ) gap> Size(H123); 2 gap> quit;