1############################################################################## 2## 3#W example7.tst KBMag Package Derek Holt 4## 5gap> START_TEST( "KBMag package: example7.tst" ); 6gap> fsa_infolevel_saved := InfoLevel( InfoFSA );; 7gap> SetInfoLevel( InfoFSA, 0 );; 8gap> rws_infolevel_saved := InfoLevel( InfoRWS );; 9gap> SetInfoLevel( InfoRWS, 0 );; 10 11gap> ## SubSection 1.15, Example 2 12gap> ## We find a free subgroup of the Fibonacci group F(2, 8). 13gap> ## This example may take about 20 minutes to run on a typical WorkStation. 14gap> F := FreeGroup( 8 );; 15gap> a:=F.1;; b:=F.2;; c:=F.3;; d:=F.4;; e:=F.5;; f:=F.6;; g:=F.7;; h:=F.8;; 16gap> G := F/[ a*b*c^-1, b*c*d^-1, c*d*e^-1, d*e*f^-1, 17> e*f*g^-1, f*g*h^-1, g*h*a^-1, h*a*b^-1 ];; 18gap> R := KBMAGRewritingSystem( G );; 19gap> S := SubgroupOfKBMAGRewritingSystem( R, [a,e] );; 20gap> AutomaticStructureOnCosetsWithSubgroupPresentation( R, S ); 21gap> P := PresentationOfSubgroupOfKBMAGRewritingSystem( R, S ); 22<fp group on the generators [ f1, f3 ]> 23gap> RelatorsOfFpGroup( P ); 24[] 25gap> Index( R, S ); 26infinity 27 28gap> ## SetInfoLevel( InfoFSA, fsa_infolevel_saved );; 29gap> ## SetInfoLevel( InfoRWS, rws_infolevel_saved );; 30gap> STOP_TEST( "example7.tst", 10000 ); 31