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Old 2018-01-15, 22:15   #2
Just call me Henry
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Sep 2007
Cambridge (GMT/BST)

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Originally Posted by lukerichards View Post
I may be missing something here, but why in the definition of Proth (k\cdot2^n + 1) and Reisel (k\cdot2^n - 1) is there the requirement that k < 2^n?

There are primes which exist when k > 2^n so is it for the purposes of more efficient primality testing?
Otherwise all odd primes would fit both definitions.
The tests that we use to prove them prime rely on these conditions.
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