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Sunday Times Teaser 2679 – Palprimes

by David Buontempo

Myself and two friends each found a five digit palindromic prime, mine being 39293.

These three primes were all different and, among them, they used all the digits from 1 to 9.

What were the other two numbers that we found?

3 Comments Leave one →
  1. brian gladman permalink

  2. ahmet cetinbudaklar permalink

    Since we are looking for two 5-digit palindromic primes and as any 2-digit and higher digit prime must necessarily end with either 1,3,7 or 9 as we already have 39293 , then the two palindromic primes must take the form of :

    1aba1 and 7cdc7 out of which by trial and error one can easily reach the answer.

  3. geoffrounce permalink

    Using Ahmet’s logic, we can find the other two palindromic primes as follows:

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