Mock AIME 4 2006-2007 Problems/Problem 5

Revision as of 22:40, 15 January 2007 by Chess64 (talk | contribs)
(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)

Problem

How many 10-digit positive integers have all digits either 1 or 2, and have two consecutive 1's?

Solution

This problem needs a solution. If you have a solution for it, please help us out by adding it.