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paulunderwood 2016-03-08 12:22

[QUOTE=PawnProver44;428391]Any other forms available? The only test that I think would Work is Lucas's Test (N-1), I do not know where I am going to calculate large exponents. Are there any mathematics libraries that would allow me to do large exponent and modular computation?
:smile:[/QUOTE]

PFGW uses the fastest library on the planet. :boxer:

science_man_88 2016-03-08 12:24

[QUOTE=PawnProver44;428364]Also, which value: k, b, n, or c would be the easiest to (substitute) find primes for[/QUOTE]

the pairings k and c, and b and c have to be coprime ( aka not share a divisor) for the form to have a chance at being prime. also all primes greater than 3 have to have remainder 1 or 5 when dividing by 6.

PawnProver44 2016-03-08 12:29

[QUOTE=paulunderwood;428392]PFGW uses the fastest library on the planet. :boxer:[/QUOTE]

Are there any other forms I could use to prove large primes besides k*b^n+-1? Just Curious.:smile:

paulunderwood 2016-03-08 12:33

[QUOTE=PawnProver44;428394]Are there any other forms I could use to prove large primes besides k*b^n+-1? Just Curious.:smile:[/QUOTE]

In general: no. As long as you know >12.5% factorisation of N^2-1, you can prove something prime in a reasonable amount of time. For example [URL="http://primes.utm.edu/primes/page.php?id=118734"]this prime.[/URL]

If k (and c) are small the underlying library is faster. :smile:

PawnProver44 2016-03-08 12:37

[QUOTE=paulunderwood;428396]In general: no. As long as you know >12.5% factorisation of N^2-1, you can prove something prime in a reasonable amount of time. For example [URL="http://primes.utm.edu/primes/page.php?id=118734"]this prime.[/URL]

If k (and c) are small the underlying library is faster. :smile:[/QUOTE]

What test would you apply?:smile:

paulunderwood 2016-03-08 12:48

[QUOTE=PawnProver44;428397]What test would you apply?:smile:[/QUOTE]

I am not sure about what you are asking. With 33.333...% of N-1 or N+1 one can use BLS; for 16.666...% of N^2-1 one can use the combined test; with 15% of the factors of N^2-1 one can prove with KP and with >12.5% of N^2-1 one can apply CHG. All can be done in a "reasonable" amount of time.

In prime searching all things are equal... for maximum speed choose k (and c) small, so that the library operates most quickly. Then run a sieve so that the elimination rate is equal to the average PRP test time of the range -- for varying n, this is about 80% of the range. Finally, run PFGW on what the sieve leaves.

PawnProver44 2016-03-08 12:52

[QUOTE=paulunderwood;428398]I am not sure about what you are asking. With 33.333...% of N-1 or N+1 one can use BLS; for 16.666...% of N^2-1 one can use the combined test; with 15% of the factors of N^2-1 one can prove with KP and with >12.5% of N^2-1 one can apply CHG. All can be done in a "reasonable" amount of time.

In prime searching all things are equal... for maximum speed choose k (and c) small, so that the library operates most quickly. Then run a sieve so that the elimination rate is equal to the average of of the range -- for varying n, this is about 80% of the range. Finally, run PFGW on what the sieve leaves.[/QUOTE]

Well in that case, here is an example: say we had large enough n for a probable prime of the form k*149^n +1 (k is large, say 3,000 digits), however we cannot factor k. Is there a way to prove k*149^n+1 prime?:smile:

paulunderwood 2016-03-08 12:56

[QUOTE=PawnProver44;428401]Well in that case, here is an example: say we had large enough n for a probable prime of the form k*149^n +1 (k is large, say 3,000 digits), however we cannot factor k. Is there a way to prove k*149^n+1 prime?:smile:[/QUOTE]

N-1 = k*149^n. So we know some of the factorisation of N-1. Apply what I said above. For k=3,000 digits, any problem numbers can be done with Primo. :smile:

PawnProver44 2016-03-08 13:01

[QUOTE=paulunderwood;428402]N-1 = k*149^n. So we know some of the factorisation of N-1. Apply what I said above. For k=3,000 digits, any problem numbers can be done with Primo. :smile:[/QUOTE]

Do we have to factor k or not in order to prove k*149^n+1 prime? Factoring k would take a long time.:smile:

paulunderwood 2016-03-08 13:02

[QUOTE=PawnProver44;428404]Do we have to factor k or not in order to prove k*149^n+1 prime? Factoring k would take a long time.:smile:[/QUOTE]

:no:

PawnProver44 2016-03-08 13:04

[QUOTE=paulunderwood;428405]:no:[/QUOTE]

Ok, I'll do some of the work to fix the variable n. The k value I am trying to find. That shouldn't be too hard, right :smile::smile::smile:


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