19081Re: [PrimeNumbers] probability of (2*p1*p2) + 1 being prime
- Sep 9, 2007--- jtrjtrjtr2001 <jtrjtrjtr2001@...> wrote:
> Hi,Well, it's just like any arbitrary number of the same size except that
> Let p2 be a large prime. We find another large random prime p1, such that
> y = (2*p1*p2) + 1.
> Is there any way, one could quantify the probability of y being a prime?
it's even, it's not divisible by p1, and it's not divisible by p2.
Therefore there's a prime density boost of (2/1) * (p1/(p1-1)) * (p2/(p2-1))
Those final two factors are effectively 1.
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