MathDB
JBMO Shortlist 2020 N7

Source: JBMO Shortlist 2020

July 4, 2021
JuniorBalkanshortlist2020number theory

Problem Statement

Prove that there doesn’t exist any prime pp such that every power of pp is a palindrome (a palindrome is a number that is read the same from the left as it is from the right; in particular, a number that ends in one or more zeros cannot be a palindrome).