Palindrome Definition

Date: 03/17/2002 at 19:54:44
From: Huy Ho
Subject: Palindromes

Do mathematicians consider single-digit numbers palindromes?

Yours,
Huy Ho

Date: 03/17/2002 at 22:12:57
From: Doctor Twe
Subject: Re: Palindromes

Hi, and thanks for writing to Dr. Math.

Mathematicians are "rules lawyers" and pay close attention to the way 
a definition is worded, so the answer to your question depends on the 
precise definition of the term "palindrome" (or palindromic number) 
you're using. If the definition says "a number that is the same when 
read from left-to-right as when read right-to-left," then I would say 
that single-digit numbers are palindromes, though I'd call them 
"trivial" cases. Eric Weisstein's World of Mathematics uses this 
definition, as shown here:

   Palindromic Number
   http://mathworld.wolfram.com/PalindromicNumber.html   

The definition could be modified, however, to exclude these trivial 
cases. For example we could define a palindromic number as "a multi-
digit number that is the same when read from left-to-right as when 
read right-to-left."

So read your book's definition of palindrome carefully, and then 
decide.

I hope this helps. If you have any more questions, write back.

- Doctor TWE, The Math Forum
  http://mathforum.org/dr.math/