Hello, I am having trouble with following proof:

Prove that all integers

2^2^(2n+1) +3 2^2^(4n+1) +7 , n = 1, 2, 3 ...

are composite.

Any help is appreciated , Thanks - Kate :)

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- Nov 5th 2007, 02:51 PMkatie07Composite number proof help
Hello, I am having trouble with following proof:

Prove that all integers

2^2^(2n+1) +3 2^2^(4n+1) +7 , n = 1, 2, 3 ...

are composite.

Any help is appreciated , Thanks - Kate :) - Nov 6th 2007, 03:51 AMtopsquark
- Nov 6th 2007, 10:26 AMJhevon
this is supposed to be $\displaystyle 2^{2^{2n + 1}} + 3 \cdot 2^{2^{4n + 1}} + 7$ right?

i'm having trouble proving this is composite for n = 1, but i'm not that good with divisibility on such a large scale, the number is huge.