number n is a d-digit palindrome in all number bases b_1,b_2,..., b_K
Source: Balkan BMO Shortlist 2016 C1
July 30, 2019
palindromesnumber theorynumber base
Problem Statement
Let positive integers and be given. Prove that there exists a positive integer and a sequence of positive integers such that the number is a -digit palindrome in all number bases .