2001 Kopeyka Coins
Source: All-Russian MO 2001 Grade 9 #5
January 2, 2012
combinatorics unsolvedcombinatorics
Problem Statement
Yura put coins of , or kopeykas in a row. It turned out that between any two -kopeyka coins there is at least one coin; between any two -kopeykas coins there are at least two coins; and between any two -kopeykas coins there are at least coins. How many -koyepkas coins could Yura put?