2009 ToT Spring Junior O P3 30digit integer with cubical blocks
Source:
March 7, 2020
minimumDigitsnumber theorycombinatorics
Problem Statement
Alex is going to make a set of cubical blocks of the same size and to write a digit on each of their faces so that it would be possible to form every -digit integer with these blocks. What is the minimal number of blocks in a set with this property? (The digits and do not turn one into another.)