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(p+5)/8 and (p+1)/4 = Prime Numbers (Posted on 2010-04-12)

Determine all possible value(s) of a prime number p such that each of (p+5)/8 and (p+1)/4 is a prime number.

See The Solution Submitted by K Sengupta

Rating: 3.0000 (1 votes)

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re: Analytical solution

Comment 5 of 5 |

(In reply to Analytical solution by Harry)

Indeed, there are only 2 valid values of p. I was thrown off by UBASIC's reporting that the smallest prime divisor of 1 is 1; but 1 is not in fact prime, so 3 is not a good value for p.

Posted by Charlie on 2010-04-13 11:35:59

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