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Old 2020-10-23, 08:02   #14
Viliam Furik
"Viliam Furík"
Jul 2018
Martin, Slovakia

24×3×7 Posts

Originally Posted by a1call View Post
Meant 2^p-1
If for any prime p
2*p+1 | 2^p-1
Then 2*p+1 is definitely prime.
The test is deterministic and computationally about as expensive as a PRP test.
This works with only k=1, thus if it divides 2p-1, it is definitely a prime factor.

Last fiddled with by Viliam Furik on 2020-10-23 at 08:04
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