268964355*2^195000-1 is prime! Time : 90.980 sec.
269367765*2^195000-1 is prime! Time : 100.803 sec.

196134045*2^195000+1 is prime!

My first prime for this project.:banana:
Too bad it does not go into to Top 5000.:sad:

Do you mean 196134045*2^195000-1 is prime too???

No the -1 is not prime

Ok :)
And why do you check for +1 first?

What is the actual ratio PRIMES / MILLIONS TESTED ?

[QUOTE=victor]Ok :)
And why do you check for +1 first?[/QUOTE]

Does it make any difference, which I check first.

[QUOTE=Citrix]Does it make any difference, which I check first.[/QUOTE]
Not at all, in fact I don't care. It was only for information.

I have an LLRnet server set up for +1 numbers, so I prefer working on +1 numbers. If I wanted to do -1 search, I will have to modify all my computers, which will be a hassle. Hence, I tested +1 primes.

Ok I computed actual ratio: it should be 47 primes on 255 Millions tested, that is

0.184313

It means we are finding a prime every 5.42 Millions.

We are slightly under previsions (between 0.2 and 0.25) .

Where The number of twins remains constant (After sieving to 83T, a range of 24.7G and 10005865 Candidates it is one twin every 13.77G), the average Gap between Primes is increasing proportiona to the ratio of the log(sieving limit).
That means sieving to 45 bit instead if 44 bit means a 45/44 larger gap between the primes. (Reason: The sieve is biased to finding twins)

The current value at 83T is a prime every 5.83M.