This is a problem of indexing / ordering relations on sets to make transformations from one to the other more expedient. It's a problem in set theory / combinatorics that relates to theories of voting and elections. The problem is at http://www.geocities.com/s349436/problem.htm Please reply to me at [EMAIL PROTECTED] (You can still include your response on the relevant newsgroup!)(more on the problem below) More specifically, it asks, given a set of options, how rankings of combinations of options from that set can be indexed to easily relate them to rankings of combinations of options from a subset. Thanks, David Catchpole.