PalindromicPrime 2006-05-27 15:58:34 2006-11-19 13:56:19 Definition palindromic number % this is the default PlanetMath preamble. as your knowledge % of TeX increases, you will probably want to edit this, but % it should be fine as is for beginners. % almost certainly you want these \usepackage{amssymb} \usepackage{amsmath} \usepackage{amsfonts} % used for TeXing text within eps files %\usepackage{psfrag} % need this for including graphics (\includegraphics) %\usepackage{graphicx} % for neatly defining theorems and propositions %\usepackage{amsthm} % making logically defined graphics %\usepackage{xypic} % there are many more packages, add them here as you need them % define commands here A prime number $p$ that in a given base $b$ is also a palindromic number. Although there are infinitely many palindromic numbers in any given base, it is not known if the same is true of palindromic primes. If $b + 1$ is prime, then it is the only palindromic prime in base $b$ to have an even number of digits; all other palindromes with an even number of digits will be multiples of $b + 1$.