MathDB
ASU 144 All Soviet Union MO 1971 digits 1 and 2 in decimal such 2^n divides

Source:

July 3, 2019
number theorypower of 2Digits

Problem Statement

Prove that for every natural nn there exists a number, containing only digits "11" and "22" in its decimal notation, that is divisible by 2n2^n ( nn-th power of two ).