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Is 2^50 + 1 a prime number?

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Is 2^50 + 1 a prime number?
posted Jul 31, 2017 by anonymous

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1 Answer

–1 vote

Yes
2^50 + 1 = prime number.

why???

Because when the exponent is even, while the base is 2, the result is always 1 digit less than prime number

how.....

(2^0) + 1 = 2...........prime
(2^2) + 1 = 5...........prime
(2^4) + 1 = 17.........prime
(2^6) + 1 = 65.........prime
(2^8) + 1 =257........prime
(2^10) + 1 = 1025...prime

Therefore if n is even, then

(2^n) + 1 = always prime

answer Jul 31, 2017 by Justine Mtafungwa
65 and 1025 are not prime...
HOW IS 65 PRIME?!?!



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