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Is there an odd prime integer $\displaystyle q$ such that $\displaystyle p= \frac{q^3+1}{2}$ is also prime?

A quick search did not find any, nor a pattern in the prime factorization of p. This is a possible quick solution to the unitary and Ree cases of ME.16954.

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7  
+1 for the wordplay. –  Willie Wong Jan 17 '11 at 17:35
    
It introduced a typo and made it illegible without mathjax. Mathjax is quite jittery and is completely overkill when html suffices. –  Jack Schmidt Jan 17 '11 at 17:36
    
Its not German sofa its Sophie Germain –  anonymous Jan 17 '11 at 17:49
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Sophie Germain was much better with primes than me. My numbers are more like a sectional sofa. One section with 2, one with (q+1)/2, and one with (qq+q+1)/2. –  Jack Schmidt Jan 17 '11 at 18:07
    
I think you mean $(qq-q+1)/2$? Also, why are you factoring out $2$? $qq\pm q+1$ is odd. –  joriki Sep 13 '12 at 9:26

1 Answer 1

up vote 20 down vote accepted

Isn't this divisble by $\displaystyle \frac{q+1}{2}$?

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Thanks, the old sum of cubes trick at it again. I'll accept in a few minutes (software imposed time limit). –  Jack Schmidt Jan 17 '11 at 17:32
    
Nice answer! :) –  The Chaz 2.0 Mar 13 '12 at 1:44
    
@TheChaz: Thanks! –  Aryabhata Mar 13 '12 at 2:03

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