program alex;
var f:text;
    i,x,z,n,r,p,d:int64;
begin
assign(f,'frac.in');reset(f);
read(f,n,p);
close(f);
assign(f,'frac.out');rewrite(f);
if p=1 then write(f,'1')
       else begin
            i:=1;
            d:=1;
            repeat
            i:=i+1;
            x:=i;
            z:=n;
            r:= x mod z;
            while r<>0 do
                  begin
                  x:=z;
                  z:=r;
                  r:=x mod z;
                  end;
            if z=1 then d:=d+1;
            until d=p;
            end;
write(f,i);
close(f);
end.