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2

Part of 1995 Poland - First Round

Problems(1)

On primes which are divisors of a difference of consecutive palindromes

Source: Poland Math Olympiad 1995 Round 1 #2

6/11/2023
A number is called a palindromic number if its decimal representation read from the left to the right is the same as read from the right to the left. Let (xn)(x_n) be the increasing sequence of all palindromic numbers. Determine all primes, which are divisors of at least one of the differences xn+1−xnx_{n+1} - x_n.