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anonymous
 4 years ago
Prove that (14^n + 4)/2 is never prime.
anonymous
 4 years ago
Prove that (14^n + 4)/2 is never prime.

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Mr.Math
 4 years ago
Best ResponseYou've already chosen the best response.5The expression you gave is never integer.

Mr.Math
 4 years ago
Best ResponseYou've already chosen the best response.5\(14^n+11\) is odd \(\forall n\in \mathbb{Z}\), which implies \(\frac{14^n+11}{2}\) is never integer and hence never prime.

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.014^n, for n>0 will always end with a 4 or a 6. And since 4+11 = 15 which is odd and 6+11 = 17 which is odd. 14^n + 11 will always be odd. And therefore as Mr.Math said, it won't be an integer and hence not a prime.

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0I never thought of that!

Mr.Math
 4 years ago
Best ResponseYou've already chosen the best response.5sorry, I was just about to change tjat\(\forall n\in \mathbb{N}\).

Mr.Math
 4 years ago
Best ResponseYou've already chosen the best response.5It's obviously not prime for n=0, because (1+11)/2=6.

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0Simply even+odd is odd hence the proof.
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