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Old 2020-07-14, 07:50   #6
JeppeSN
 
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"Jeppe"
Jan 2016
Denmark

16610 Posts
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To make what everybody else said already, more explicit:

Your exponent 283243137 is divisible by 3. So 283243137 = 3*N.

Then the number you propose, namely 2^283243137 - 1, is equal to 2^(3*N) - 1 = (2^3)^N - 1. And that will be divisible by 2^3 - 1 = 7. So the number you suggest, is divisible by 7 (because your exponent is divisible by 3).

/JeppeSN
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