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Count the palindromes (Posted on 2015-11-11) Difficulty: 2 of 5
N is both a a palindrome and a sum of eleven consecutive positive integers.

How many possible values for N exist below 80,000?
Please provide the lowest and the highest samples.

No Solution Yet Submitted by Ady TZIDON    
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re(2): Simplifying the question | Comment 5 of 7 |
(In reply to re: Simplifying the question by Ady TZIDON)

Oh, I don't solve perplexus problems with a computer program (except sometimes I do use Excel).  I was thinking about how to tackle it analytically.


Recognizing that all and only numbers divisible by 11 are the sum of eleven consecutive integers makes it trivial to analytically count the qualifying palindromes with an even number of digits (because they all qualify).  And it may help to count the palindromes with an odd number of digits, although I am not there yet. 

  Posted by Steve Herman on 2015-11-11 14:36:00
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