{frac}

var f,g:text;
    n,p,nr:int64;

procedure citire;
begin
assign(f,'frac.in'); reset(f);
readln(f,n,p);
close(f);
end;

function cmmdc(a,b:int64):int64;
var r:int64;
begin

while b<>0 do
      begin
      r:=a mod b;
      a:=b;
      b:=r;
      end;

cmmdc:=a;

end;

procedure rezolvare;
var ok:boolean;
    x:int64;
begin

assign(g,'frac.out'); rewrite(g);

ok:=false;
x:=1;

while not ok do
      begin
      if cmmdc(x,n)=1 then
         begin
         inc(nr);
         if nr=p then
            begin
            ok:=true;
            writeln(g,x);
            close(g);
            exit;
            end;
         end;
      inc(x);
      end;
end;

begin
citire;
rezolvare;
end.