If what you are saying is that the problem can be expanded, and the results are the same, I do not believe this to be true, at least not obviously so. Jon Perry perry at globalnet.co.uk http://www.users.globalnet.co.uk/~perry/maths/ http://www.users.globalnet.co.uk/~perry/DIVMenu/ BrainBench MVP for HTML and JavaScript http://www.brainbench.com