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This problem was inspired by the infamous problem 6 in the 1988 Math Olympiad:

When is a2+b2 divisible by (ab+1)2 where a and b are non-negative integers?

(No Solution Yet, 1 Comments) Submitted on 2018-06-17 by Daniel   
Difficulty: 2 of 5 Bonus: Emir P. Prime (in Numbers) Rating: 4.00

Can you identify the five-digit sphenic palindrome

  • where the sum of its digits is a palindromic prime,
  • where of one its factors is a multi-digit palindromic prime, and
  • the sum of its factors is also a palindromic prime?

Can you identify any other sphenic palindrome that has these characteristics?

A sphenic number is a positive integer and product of three distinct primes.
A palindromic number is a number that is the same when written forwards or backwards.

(Solution Posted, 4 Comments) Submitted on 2007-04-19 by Dej Mar   
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