If you cannot see anything above, then your browser probably doesn't support the class BigInteger, which is included in JDK 1.1. You can run this applet as a standalone program (under JDK 1.1.3 or higher), or using appletviewer. I tested this applet with HotJava 1.1.2 generic browser, it works well. Netscape 4.04 is not JDK 1.1-compartible, under it the applet doesn't work :-(.
The source text of this applet.