public abstract class BadSeries
    implements DoubleTerm, DoubleNext {

    public static void main(String argv[]) {
	BadSeries myBadSeries
	    = new PiOver8BadSeries();
	System.out.println(
	  "8.0 * myBadSeries.sum(1.0,1000.0) = "
	  // type error in next line
	  + (8.0 * myBadSeries.sum(1.0, 1000.0)));
    }
}