# 68 arithmetic/digits/palindrome.p

## Description

This article is from the Puzzles FAQ,
by Chris Cole chris@questrel.questrel.com and Matthew Daly
mwdaly@pobox.com with numerous contributions by others.

# 68 arithmetic/digits/palindrome.p

Does the series formed by adding a number to its reversal always end in

a palindrome?

arithmetic/digits/palindrome.s

This is not known.

If you start with 196, after 9480000 iterations you get a 3924257-digit

non-palindromic number. However, there is no known proof that you will

never get a palindrome.

The statement is provably false for binary numbers. Roland Sprague has

shown that 10110 starts a series that never goes palindromic.

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