#We find all primitive subgroups of $GL(8,5)$ with parameters $e=4$, $a=2$. #In the notations of Theorem 5.1, if $H\leq GL(8,5)$ is a primitive solvable subgroup, then it possesses a series #$$1 e:=4;; p:=5;; d:=8;; a:=2;; #Now we generate the list of all primitive subgroups in $GL(8,5)$, using standart function of the package IRREDSOL gap> l0:=AllIrreducibleSolvableMatrixGroups(Degree,d,Field,GF(p),IsPrimitiveMatrixGroup,true);; #In this list we choose subgroups, whose order is divisible by the order of $F$ in the notations of Theorem 5.1 gap> l1:=Filtered(l0,x-> (Order(x) mod ((p^a-1)*e*e)) = 0);; #In view of Lemma 5.3, we choose subgroups satisfying $\vert A/F\vert\in \{20,72\}$ and collect these subgroups in the list l2. gap> l2:=Filtered(l1,x-> (Order(x)/((p^a-1)*e*e)) in [20,72, 2*20,2*72]);; #Now we run the following loop. Each entry of the list result has three items: the first is the #number of the group in the list gens, the second is the order of the group, and the third is the order of the stabilizer of v in H. #If the order of the stabilizer is 1, then |v^H=|H| and Corollary 2.5 can be applied. gap> z:=Z(5);; v:=[z,0*z,z^2,z^4,0*z,0*z,z,0*z];; gap> result:=[];; gap> i:=0;; gap> for j in l2 do > n:=Size(j);; > m:=Size(v^j); > i:=i+1; > Append(result,[[i,n,n/m]]); > Display([i,n,n/m]); > od; [ 1, 55296, 2 ] [ 2, 27648, 2 ] [ 3, 27648, 1 ] [ 4, 27648, 1 ] [ 5, 27648, 2 ] [ 6, 27648, 2 ] [ 7, 27648, 1 ] [ 8, 27648, 1 ] [ 9, 27648, 2 ] [ 10, 27648, 2 ] [ 11, 27648, 2 ] [ 12, 27648, 1 ] [ 13, 27648, 1 ] [ 14, 27648, 1 ] [ 15, 27648, 1 ] [ 16, 15360, 1 ] [ 17, 7680, 1 ] [ 18, 7680, 1 ] [ 19, 7680, 1 ] [ 20, 7680, 1 ] [ 21, 7680, 1 ] [ 22, 7680, 1 ] [ 23, 27648, 1 ] [ 24, 55296, 2 ] [ 25, 55296, 1 ] [ 26, 55296, 1 ] [ 27, 27648, 2 ] [ 28, 27648, 1 ] [ 29, 27648, 2 ] [ 30, 27648, 2 ] [ 31, 27648, 1 ] [ 32, 27648, 1 ] [ 33, 27648, 1 ] [ 34, 27648, 1 ] [ 35, 55296, 2 ] [ 36, 55296, 2 ] [ 37, 55296, 1 ] [ 38, 55296, 1 ] [ 39, 27648, 2 ] [ 40, 27648, 2 ] [ 41, 27648, 1 ] [ 42, 27648, 1 ] [ 43, 15360, 1 ] [ 44, 7680, 1 ] [ 45, 7680, 1 ] [ 46, 7680, 1 ] [ 47, 15360, 1 ] [ 48, 15360, 1 ] [ 49, 7680, 1 ] [ 50, 7680, 1 ] [ 51, 7680, 1 ] [ 52, 7680, 1 ] [ 53, 27648, 2 ] [ 54, 55296, 2 ] [ 55, 27648, 2 ] [ 56, 55296, 2 ] [ 57, 55296, 2 ] [ 58, 27648, 1 ] [ 59, 27648, 1 ] [ 60, 27648, 1 ] [ 61, 27648, 2 ] [ 62, 7680, 1 ] #Now we choose groups such that |v^H|<>|H| in the list res1 gap> res1:=Filtered(result,x->x[3]<>1);; gap> Size(res1); 21 #Now we define a function which check, if the $2$-closure of a group $g$ aacting on $v^g$ is equal to $g$, so that Lemma 4.4 can be applied. This function uses #COCO2P package gap> twoc:=function(g,v) > local h,a; > h:=Action(g,v^g,OnRight); > a:=AutomorphismGroup(ColorGraph(h)); > return IsSubgroup(a,h) and IsSubgroup(h,a); > end; function( g, v ) ... end #We define the vector $v$. #We check that Lemma 4.4 is satisfied for all g in the list l2, i.e. that every subgroup g in the list l2 is 2-closed on v^g. gap> v:=[z,0*z,z^2,z^4,0*z,0*z,0*z,0*z];; gap> result1:=[];; gap> for j in res1 do > tf:=twoc(l2[j[1]],v);; > Append(result,[[j[1],j[2],tf]]);; > Display([j[1],j[2],tf]); > od; [ 1, 55296, true ] [ 2, 27648, true ] [ 5, 27648, true ] [ 6, 27648, true ] [ 9, 27648, true ] [ 10, 27648, true ] [ 11, 27648, true ] [ 24, 55296, true ] [ 27, 27648, true ] [ 29, 27648, true ] [ 30, 27648, true ] [ 35, 55296, true ] [ 36, 55296, true ] [ 39, 27648, true ] [ 40, 27648, true ] [ 53, 27648, true ] [ 54, 55296, true ] [ 55, 27648, true ] [ 56, 55296, true ] [ 57, 55296, true ] [ 61, 27648, true ]