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From primes to palindrome (Posted on 2012-03-24) Difficulty: 2 of 5
The product of the first X primes divided by Y results in a non-trivial (more than a single digit) palindrome number.
Find a solution(or solutions?) for integers X and Y.

See The Solution Submitted by Ady TZIDON    
Rating: 5.0000 (2 votes)

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Solution All solutions Comment 7 of 7 |
https://oeis.org/A071251

I suppose I should say all integer solutions (nice one Dej Mar)

When you divide out some of the prime factors of X you are left with a squarefree number.  Every square free palindrome is then possible to construct .

To find X and Y for a given number in the above linked sequence just factor the number.  X is the number of primes up to the largest factor.  Y is the product of the missing primes.

For example 66 = 2*3*11
The primes up to 11 are 2,3,5,7,11 so there are X=5 primes, the missing ones are 5 and 7 so Y=35


  Posted by Jer on 2012-03-24 22:49:03
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