"Source: Text/Group/GrpFPInt.text";
"Line: 1778";
"Date: Thu Sep 25 14:47:45 2025";
"Main: Fri Sep 26 14:29:19 2025";
// original file: Text/Group/GrpFPInt.text, line: 1778
// Example: H79E21 ()
print "Example: H79E21";
ei := GetEchoInput();
SetEchoInput(true);
L27<x, y> := FPGroup< x, y | x^3 = 1, y^3 = 1, (x*y)^4 = 1,
                        (y*y^x)^2 = y^x*y >;          
H<a, b> := sub<L27 | (x*y)^2, y >;
Index(L27, H);
assert $1 eq 1;
H;
Rewrite(L27, ~H);
H;
Order(DeleteRelation(H, 5)) eq Order(H);
assert $1;
SetEchoInput(ei);
