Alex, you have a great website and doing a tremendous job. Great stuff for everybody.

BTW, is there a formal reference (easily accessible) for this proof?

Thanks again,

Peter

P.S. Actually could not upload my file. It asked me to login first (but where?).

thank you for the kind words. "Login" is the first item in the menu bar when you go to the Conferences page. But you can send the file directly to me: alexb at cut-the-knot.com. If you do, give a full name.