usemakro("idpot_tools");

Group:=listprompt("Select a structure", structures);

binary_operations:=emptyset;

for op in operations(Group) do 
  if equal(arity(op),2) then additem(binary_operations, op) else noop endif
endfor;

if >(card(binary_operations),0) then
  op:=listprompt("Select a binary operation", binary_operations);
  write("Idempotent unary polynoms a*x^n in <"); write(Group); write(",");write(op);writeln(">");
  for n in card(Group) do
    if >(n,0) then 
      for g in Group do
        poly:=lambda(x) op(g,power_op(op,n,x)) endlambda;
        if idempotent(poly,Group) then write("a:=");write(g);write("     n:=");writeln(n)
        else noop endif
      endfor
    else noop endif
  endfor
else writeln("No binary operations!") endif;