210

Part of 1975 All Soviet Union Mathematical Olympiad

Problems(1)

ASU 210 All Soviet Union MO 1975 2^n digit number with only 1,2 differ

Source:

Prove that it is possible to find

2^{n+1}

2^n

digit numbers containing only "

1

2

" as digits, such that every two of them distinguish at least in

2^{n-1}

number theorycombinatoricsDigits