Dear Rahul, You need to call "Subgroup" (enter ?Subgroup in GAP to see the manual). For example,
gap> F:=FreeGroup("a","b"); <free group on the generators [ a, b ]> gap> AssignGeneratorVariables(F); #I Assigned the global variables [ a, b ] gap> G:=F/[a^4,b^2,b*a*b*a]; <fp group on the generators [ a, b ]> gap> g:=GeneratorsOfGroup(G); [ a, b ] gap> Subgroup(G,[g[1]*g[2]]); Group([ a*b ]) gap> Size(last); 2 gap> Subgroup(G,[g[1]]); Group([ a ]) gap> Size(last); 4 Note that variables a and b above are generators of the free group and not of the group G, so I can't use Subgroup(G,[a*b]) unless I redefine them. Hope this helps, Alexander On 1 Feb 2011, at 13:50, rahul kitture wrote: > Dear Sir, > > A small question regarding subgroup with generators > When doing computations of groups on GAP, with the group given by generators > and relations, how can we find subgroup generated by some elements of group? > (i.e. how can we obtain subgroup generated by specific elements of group?) > > > > > > -- > Rahul D. Kitture > Junior Research Fellow, > Bhaskaracharya Pratishthana > (Research Institute for Matmematics) > www.bprim.org > Pune: 411 004 (India) _______________________________________________ Forum mailing list Forum@mail.gap-system.org http://mail.gap-system.org/mailman/listinfo/forum