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Message boards : Generalized Fermat Prime Search : Generalized Fermat with odd base?

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321 LLR Ruby: Earned 2,000,000 credits (2,092,823)Cullen LLR Ruby: Earned 2,000,000 credits (2,289,208)ESP LLR Amethyst: Earned 1,000,000 credits (1,445,099)Generalized Cullen/Woodall LLR Ruby: Earned 2,000,000 credits (2,180,764)PPS LLR Amethyst: Earned 1,000,000 credits (1,225,852)PSP LLR Ruby: Earned 2,000,000 credits (2,064,832)SoB LLR Amethyst: Earned 1,000,000 credits (1,669,219)SR5 LLR Ruby: Earned 2,000,000 credits (2,065,004)SGS LLR Amethyst: Earned 1,000,000 credits (1,412,461)TRP LLR Ruby: Earned 2,000,000 credits (2,089,856)Woodall LLR Ruby: Earned 2,000,000 credits (2,112,258)321 Sieve (suspended) Ruby: Earned 2,000,000 credits (2,107,153)PPS Sieve Turquoise: Earned 5,000,000 credits (5,096,952)AP 26/27 Turquoise: Earned 5,000,000 credits (5,150,782)GFN Turquoise: Earned 5,000,000 credits (7,510,843)WW Double Silver: Earned 200,000,000 credits (243,048,000)PSA Amethyst: Earned 1,000,000 credits (1,022,470)
Message 142689 - Posted: 25 Aug 2020 | 17:59:15 UTC

I saw on OEIS A253242 that generalized Fermat number with odd base b are defined as (b^2^n + 1)/2.

Is it possible to efficiently test these for primality with genefer?

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321 LLR Gold: Earned 500,000 credits (632,096)Cullen LLR Bronze: Earned 10,000 credits (82,217)ESP LLR Bronze: Earned 10,000 credits (16,570)Generalized Cullen/Woodall LLR Bronze: Earned 10,000 credits (12,551)PPS LLR Ruby: Earned 2,000,000 credits (3,098,543)PSP LLR Silver: Earned 100,000 credits (106,263)SoB LLR Silver: Earned 100,000 credits (258,849)SR5 LLR Bronze: Earned 10,000 credits (59,499)SGS LLR Silver: Earned 100,000 credits (148,878)TRP LLR Silver: Earned 100,000 credits (195,905)Woodall LLR Bronze: Earned 10,000 credits (40,424)321 Sieve (suspended) Turquoise: Earned 5,000,000 credits (5,001,667)AP 26/27 Bronze: Earned 10,000 credits (72,774)GFN Gold: Earned 500,000 credits (502,872)WW Bronze: Earned 10,000 credits (12,000)
Message 142692 - Posted: 25 Aug 2020 | 18:47:51 UTC - in response to Message 142689.

I don't think there's any fast primality test known for these numbers. Your best bet would be to run a PRP test (which can be done quickly for numbers of any form), and if it's a PRP, try to prove it either with ECPP or by factoring p-1 = (b^2^n - 1)/2 as much as possible.

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Found 1 prime in the 2020 Tour de Primes321 LLR Gold: Earned 500,000 credits (529,293)Cullen LLR Gold: Earned 500,000 credits (611,298)ESP LLR Silver: Earned 100,000 credits (174,818)Generalized Cullen/Woodall LLR Bronze: Earned 10,000 credits (35,236)PPS LLR Jade: Earned 10,000,000 credits (13,219,174)PSP LLR Silver: Earned 100,000 credits (428,457)SoB LLR Silver: Earned 100,000 credits (466,812)SR5 LLR Silver: Earned 100,000 credits (145,419)SGS LLR Silver: Earned 100,000 credits (112,277)TRP LLR Silver: Earned 100,000 credits (342,501)Woodall LLR Silver: Earned 100,000 credits (109,455)321 Sieve (suspended) Silver: Earned 100,000 credits (175,037)PPS Sieve Bronze: Earned 10,000 credits (10,113)AP 26/27 Bronze: Earned 10,000 credits (12,129)GFN Ruby: Earned 2,000,000 credits (2,059,478)WW Turquoise: Earned 5,000,000 credits (9,640,000)PSA Turquoise: Earned 5,000,000 credits (7,614,290)
Message 142694 - Posted: 25 Aug 2020 | 19:35:12 UTC

You can find a bunch of these with this search: http://www.primenumbers.net/prptop/searchform.php?form=%28b%5En%2B1%29%2F2

For most of them, it has never been proved they are prime. PRP Top is a list of probable primes for which it is not practically possible to prove their primality.

/JeppeSN

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321 LLR Ruby: Earned 2,000,000 credits (2,092,823)Cullen LLR Ruby: Earned 2,000,000 credits (2,289,208)ESP LLR Amethyst: Earned 1,000,000 credits (1,445,099)Generalized Cullen/Woodall LLR Ruby: Earned 2,000,000 credits (2,180,764)PPS LLR Amethyst: Earned 1,000,000 credits (1,225,852)PSP LLR Ruby: Earned 2,000,000 credits (2,064,832)SoB LLR Amethyst: Earned 1,000,000 credits (1,669,219)SR5 LLR Ruby: Earned 2,000,000 credits (2,065,004)SGS LLR Amethyst: Earned 1,000,000 credits (1,412,461)TRP LLR Ruby: Earned 2,000,000 credits (2,089,856)Woodall LLR Ruby: Earned 2,000,000 credits (2,112,258)321 Sieve (suspended) Ruby: Earned 2,000,000 credits (2,107,153)PPS Sieve Turquoise: Earned 5,000,000 credits (5,096,952)AP 26/27 Turquoise: Earned 5,000,000 credits (5,150,782)GFN Turquoise: Earned 5,000,000 credits (7,510,843)WW Double Silver: Earned 200,000,000 credits (243,048,000)PSA Amethyst: Earned 1,000,000 credits (1,022,470)
Message 142697 - Posted: 26 Aug 2020 | 7:14:30 UTC

I suspected it might be problematic the prove their primality, but wasn't sure.

The background ist that I'm trying to find a use for a cheaper card like a 1650. From what I read here it will likely not produce any 1st. While a certain amount of double checking is of course no problem, without any 1st the search feels a bit pointless. So I thought I might use it for manual search of some more exotic primes.

Is there anything else that could be done specifically with a GPU?

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Discovered 1 mega prime321 LLR Gold: Earned 500,000 credits (506,806)Cullen LLR Silver: Earned 100,000 credits (112,212)ESP LLR Silver: Earned 100,000 credits (255,803)Generalized Cullen/Woodall LLR Gold: Earned 500,000 credits (509,419)PPS LLR Ruby: Earned 2,000,000 credits (2,001,172)PSP LLR Gold: Earned 500,000 credits (616,940)SoB LLR Gold: Earned 500,000 credits (533,625)SR5 LLR Silver: Earned 100,000 credits (108,281)SGS LLR Gold: Earned 500,000 credits (501,474)TRP LLR Silver: Earned 100,000 credits (146,999)Woodall LLR Silver: Earned 100,000 credits (117,864)321 Sieve (suspended) Gold: Earned 500,000 credits (506,814)Generalized Cullen/Woodall Sieve (suspended) Bronze: Earned 10,000 credits (30,033)PPS Sieve Ruby: Earned 2,000,000 credits (2,808,043)AP 26/27 Amethyst: Earned 1,000,000 credits (1,273,545)GFN Ruby: Earned 2,000,000 credits (3,590,656)WW Turquoise: Earned 5,000,000 credits (6,148,000)PSA Silver: Earned 100,000 credits (373,034)
Message 142698 - Posted: 26 Aug 2020 | 7:43:44 UTC - in response to Message 142697.

I suspected it might be problematic the prove their primality, but wasn't sure.

The background ist that I'm trying to find a use for a cheaper card like a 1650. From what I read here it will likely not produce any 1st. While a certain amount of double checking is of course no problem, without any 1st the search feels a bit pointless. So I thought I might use it for manual search of some more exotic primes.

Is there anything else that could be done specifically with a GPU?


PPS SV, AP, incoming WW. Or GFN14 which is ending soon.
____________
SHSIDElectronicsGroup@outlook.com

waiting for a TdP prime...
Proth "SoB": 44243*2^440969+1


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321 LLR Ruby: Earned 2,000,000 credits (2,092,823)Cullen LLR Ruby: Earned 2,000,000 credits (2,289,208)ESP LLR Amethyst: Earned 1,000,000 credits (1,445,099)Generalized Cullen/Woodall LLR Ruby: Earned 2,000,000 credits (2,180,764)PPS LLR Amethyst: Earned 1,000,000 credits (1,225,852)PSP LLR Ruby: Earned 2,000,000 credits (2,064,832)SoB LLR Amethyst: Earned 1,000,000 credits (1,669,219)SR5 LLR Ruby: Earned 2,000,000 credits (2,065,004)SGS LLR Amethyst: Earned 1,000,000 credits (1,412,461)TRP LLR Ruby: Earned 2,000,000 credits (2,089,856)Woodall LLR Ruby: Earned 2,000,000 credits (2,112,258)321 Sieve (suspended) Ruby: Earned 2,000,000 credits (2,107,153)PPS Sieve Turquoise: Earned 5,000,000 credits (5,096,952)AP 26/27 Turquoise: Earned 5,000,000 credits (5,150,782)GFN Turquoise: Earned 5,000,000 credits (7,510,843)WW Double Silver: Earned 200,000,000 credits (243,048,000)PSA Amethyst: Earned 1,000,000 credits (1,022,470)
Message 142701 - Posted: 26 Aug 2020 | 12:24:23 UTC - in response to Message 142698.
Last modified: 26 Aug 2020 | 12:24:38 UTC

I'd have preferred something that Primegrid isn't already working on, so I don't accidentally do numbers that are or will be covered.

For primes of the form b^2^n + 2 it's also not easy to prove their primality?

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Discovered the World's First base 116 Generalized Cullen prime!!!Discovered 28 mega primesEliminated 7 conjecture "k"sDiscovered 1 Sophie Germain pairDiscovered 2 Fermat divisors2012 Tour de Primes highest prime count2012 Tour de Primes most Mountain Stage primes2015 Tour de Primes highest prime count2016 Tour de Primes highest prime countFound 23 primes in the 2018 Tour de PrimesFound 1 mega prime in the 2018 Tour de PrimesFound 2 primes in the 2018 Tour de Primes Mountain Stage2019 Tour de Primes highest prime countFound 22 primes in the 2019 Tour de Primes2020 Tour de Primes highest prime scoreFound 21 primes in the 2020 Tour de PrimesFound 4 mega primes in the 2020 Tour de PrimesFound 8 primes in the 2021 Tour de PrimesFound 1 mega prime in the 2021 Tour de Primes321 LLR Double Silver: Earned 200,000,000 credits (201,403,028)Cullen LLR Double Silver: Earned 200,000,000 credits (201,409,561)ESP LLR Double Silver: Earned 200,000,000 credits (214,825,147)Generalized Cullen/Woodall LLR Double Bronze: Earned 100,000,000 credits (133,750,194)PPS LLR Double Gold: Earned 500,000,000 credits (735,628,070)PSP LLR Double Bronze: Earned 100,000,000 credits (181,223,975)SoB LLR Double Silver: Earned 200,000,000 credits (207,028,068)SR5 LLR Double Silver: Earned 200,000,000 credits (214,437,634)SGS LLR Double Silver: Earned 200,000,000 credits (205,718,935)TPS LLR (retired) Silver: Earned 100,000 credits (235,439)TRP LLR Double Silver: Earned 200,000,000 credits (201,215,056)Woodall LLR Double Silver: Earned 200,000,000 credits (201,651,344)321 Sieve (suspended) Double Silver: Earned 200,000,000 credits (235,451,253)Cullen/Woodall Sieve (suspended) Emerald: Earned 50,000,000 credits (83,794,448)Generalized Cullen/Woodall Sieve (suspended) Double Silver: Earned 200,000,000 credits (285,139,652)PPS Sieve Double Ruby: Earned 2,000,000,000 credits (2,731,606,455)Sierpinski (ESP/PSP/SoB) Sieve (suspended) Double Silver: Earned 200,000,000 credits (203,523,358)TRP Sieve (suspended) Double Silver: Earned 200,000,000 credits (201,489,157)AP 26/27 Double Silver: Earned 200,000,000 credits (442,961,701)GFN Double Ruby: Earned 2,000,000,000 credits (2,148,298,569)WW Double Ruby: Earned 2,000,000,000 credits (2,469,152,000)PSA Double Silver: Earned 200,000,000 credits (259,058,048)
Message 142702 - Posted: 26 Aug 2020 | 12:56:55 UTC - in response to Message 142697.


The background ist that I'm trying to find a use for a cheaper card like a 1650. From what I read here it will likely not produce any 1st. While a certain amount of double checking is of course no problem, without any 1st the search feels a bit pointless. So I thought I might use it for manual search of some more exotic primes.

Is there anything else that could be done specifically with a GPU?


I think that your information isn't quite accurate. A GTX 1650 has a similar runtime to a GTX 1060 3GB card. I have a couple of those running the current AP27 project and getting a "first" rate of somewhere in the 25% to 40% range. You will also find it does well on projects like GFN15 with the shorter work and where, without some manual configuration interventions, high-end cards work very inefficiently compared to cards like the 1650. You might also try GFN17 Low--the smaller number of competing GPUs on this less popular subproject will mean a higher "first" rate for cards like the 1650.

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Message 142705 - Posted: 26 Aug 2020 | 15:28:20 UTC - in response to Message 142701.

For primes of the form b^2^n + 2 it's also not easy to prove their primality?

No, see Finding primes & proving primality.

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Discovered 1 mega prime321 LLR Gold: Earned 500,000 credits (506,806)Cullen LLR Silver: Earned 100,000 credits (112,212)ESP LLR Silver: Earned 100,000 credits (255,803)Generalized Cullen/Woodall LLR Gold: Earned 500,000 credits (509,419)PPS LLR Ruby: Earned 2,000,000 credits (2,001,172)PSP LLR Gold: Earned 500,000 credits (616,940)SoB LLR Gold: Earned 500,000 credits (533,625)SR5 LLR Silver: Earned 100,000 credits (108,281)SGS LLR Gold: Earned 500,000 credits (501,474)TRP LLR Silver: Earned 100,000 credits (146,999)Woodall LLR Silver: Earned 100,000 credits (117,864)321 Sieve (suspended) Gold: Earned 500,000 credits (506,814)Generalized Cullen/Woodall Sieve (suspended) Bronze: Earned 10,000 credits (30,033)PPS Sieve Ruby: Earned 2,000,000 credits (2,808,043)AP 26/27 Amethyst: Earned 1,000,000 credits (1,273,545)GFN Ruby: Earned 2,000,000 credits (3,590,656)WW Turquoise: Earned 5,000,000 credits (6,148,000)PSA Silver: Earned 100,000 credits (373,034)
Message 142706 - Posted: 26 Aug 2020 | 15:33:22 UTC - in response to Message 142701.

I'd have preferred something that Primegrid isn't already working on, so I don't accidentally do numbers that are or will be covered.

For primes of the form b^2^n + 2 it's also not easy to prove their primality?


There really isn't much work optimized for GPUs. YOu could try searching for GIMPS with mlucas.

Aside from that, Scott is quite correct. GFN15 and 17low can be run efficiently on 1650s, the better option would be 1650Super though if you want to run AP or other PG subprojects.
____________
SHSIDElectronicsGroup@outlook.com

waiting for a TdP prime...
Proth "SoB": 44243*2^440969+1


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321 LLR Ruby: Earned 2,000,000 credits (2,092,823)Cullen LLR Ruby: Earned 2,000,000 credits (2,289,208)ESP LLR Amethyst: Earned 1,000,000 credits (1,445,099)Generalized Cullen/Woodall LLR Ruby: Earned 2,000,000 credits (2,180,764)PPS LLR Amethyst: Earned 1,000,000 credits (1,225,852)PSP LLR Ruby: Earned 2,000,000 credits (2,064,832)SoB LLR Amethyst: Earned 1,000,000 credits (1,669,219)SR5 LLR Ruby: Earned 2,000,000 credits (2,065,004)SGS LLR Amethyst: Earned 1,000,000 credits (1,412,461)TRP LLR Ruby: Earned 2,000,000 credits (2,089,856)Woodall LLR Ruby: Earned 2,000,000 credits (2,112,258)321 Sieve (suspended) Ruby: Earned 2,000,000 credits (2,107,153)PPS Sieve Turquoise: Earned 5,000,000 credits (5,096,952)AP 26/27 Turquoise: Earned 5,000,000 credits (5,150,782)GFN Turquoise: Earned 5,000,000 credits (7,510,843)WW Double Silver: Earned 200,000,000 credits (243,048,000)PSA Amethyst: Earned 1,000,000 credits (1,022,470)
Message 142708 - Posted: 26 Aug 2020 | 16:44:53 UTC

Actually, I wanted to try some manual searching. But since I also didn't want to move a CPU away from Primegrid, I thought of buying a relatively cheap GPU and use that.

But apparently all primes that can be efficiently searched for by GPU are already covered by Primegrid... :)

One last idea, is there a GPU software for Proth primes? I couldn't find any though.

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Discovered 8 mega primesFound 5 primes in the 2020 Tour de PrimesFound 2 mega primes in the 2020 Tour de PrimesFound 4 primes in the 2021 Tour de PrimesFound 2 mega primes in the 2021 Tour de Primes321 LLR Sapphire: Earned 20,000,000 credits (20,020,701)Cullen LLR Sapphire: Earned 20,000,000 credits (20,174,451)ESP LLR Sapphire: Earned 20,000,000 credits (23,496,803)Generalized Cullen/Woodall LLR Sapphire: Earned 20,000,000 credits (20,197,125)PPS LLR Emerald: Earned 50,000,000 credits (61,332,778)PSP LLR Emerald: Earned 50,000,000 credits (51,069,305)SoB LLR Sapphire: Earned 20,000,000 credits (39,168,048)SR5 LLR Sapphire: Earned 20,000,000 credits (20,183,763)SGS LLR Sapphire: Earned 20,000,000 credits (20,482,069)TRP LLR Sapphire: Earned 20,000,000 credits (20,307,419)Woodall LLR Sapphire: Earned 20,000,000 credits (22,371,625)321 Sieve (suspended) Sapphire: Earned 20,000,000 credits (20,380,527)Cullen/Woodall Sieve (suspended) Gold: Earned 500,000 credits (744,531)Generalized Cullen/Woodall Sieve (suspended) Turquoise: Earned 5,000,000 credits (5,007,004)PPS Sieve Double Gold: Earned 500,000,000 credits (575,271,481)TRP Sieve (suspended) Bronze: Earned 10,000 credits (21,181)AP 26/27 Sapphire: Earned 20,000,000 credits (20,845,708)GFN Double Silver: Earned 200,000,000 credits (482,041,720)WW Double Amethyst: Earned 1,000,000,000 credits (1,365,432,000)
Message 142709 - Posted: 26 Aug 2020 | 17:03:43 UTC - in response to Message 142708.
Last modified: 26 Aug 2020 | 17:06:34 UTC

One last idea, is there a GPU software for Proth primes? I couldn't find any though.

This may answer the question, or it may not (my money is on not because I am not confident of the subject to know):
http://www.primegrid.com/forum_thread.php?id=9229

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Message 142710 - Posted: 26 Aug 2020 | 17:26:16 UTC - in response to Message 142708.

One last idea, is there a GPU software for Proth primes? I couldn't find any though.

Yes, proth20 binaries and proth20 sources.

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321 LLR Ruby: Earned 2,000,000 credits (2,092,823)Cullen LLR Ruby: Earned 2,000,000 credits (2,289,208)ESP LLR Amethyst: Earned 1,000,000 credits (1,445,099)Generalized Cullen/Woodall LLR Ruby: Earned 2,000,000 credits (2,180,764)PPS LLR Amethyst: Earned 1,000,000 credits (1,225,852)PSP LLR Ruby: Earned 2,000,000 credits (2,064,832)SoB LLR Amethyst: Earned 1,000,000 credits (1,669,219)SR5 LLR Ruby: Earned 2,000,000 credits (2,065,004)SGS LLR Amethyst: Earned 1,000,000 credits (1,412,461)TRP LLR Ruby: Earned 2,000,000 credits (2,089,856)Woodall LLR Ruby: Earned 2,000,000 credits (2,112,258)321 Sieve (suspended) Ruby: Earned 2,000,000 credits (2,107,153)PPS Sieve Turquoise: Earned 5,000,000 credits (5,096,952)AP 26/27 Turquoise: Earned 5,000,000 credits (5,150,782)GFN Turquoise: Earned 5,000,000 credits (7,510,843)WW Double Silver: Earned 200,000,000 credits (243,048,000)PSA Amethyst: Earned 1,000,000 credits (1,022,470)
Message 142742 - Posted: 28 Aug 2020 | 7:06:45 UTC
Last modified: 28 Aug 2020 | 7:08:12 UTC

Nick, thanks, I forgot about that completely... :) So, LLR is a waste of GPU. But PRP testing of GFN is working with high efficiency. Can the same be applied to Proth or Riesel?

This would speed up work considerably on almost all PG subprojects.


Yves, thanks for the link, is it doing LLR or PRP? I assume LLR? Will it be possible to include a PRP test? I don't have an OpenCL card, but would certainly be willing to get one if it would help in development.


edit: Btw, I asked a similar question over at mersenneforum.org where the idea of using GPU for PRP testing came up.

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Message 142748 - Posted: 28 Aug 2020 | 8:12:00 UTC - in response to Message 142742.
Last modified: 28 Aug 2020 | 8:20:59 UTC

Yves, thanks for the link, is it doing LLR or PRP? I assume LLR? Will it be possible to include a PRP test?

Neither LLR nor PRP but Proth's theorem.
For numbers of the form k·2n + 1, k < 2n, Proth's test is as fast as a prp test and is a primality proof. proth20 implements this test with Gerbicz error checking.
Gerbicz algorithm doesn't work with LLR because of the -2 term. Then if you want to search for primes of the form k·2n - 1 and implement Gerbicz error checking, you must do a PRP test to eliminate composite numbers. Only the final primality proof on prp numbers will be LLR test.

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Discovered the World's First base 116 Generalized Cullen prime!!!Discovered 28 mega primesEliminated 7 conjecture "k"sDiscovered 1 Sophie Germain pairDiscovered 2 Fermat divisors2012 Tour de Primes highest prime count2012 Tour de Primes most Mountain Stage primes2015 Tour de Primes highest prime count2016 Tour de Primes highest prime countFound 23 primes in the 2018 Tour de PrimesFound 1 mega prime in the 2018 Tour de PrimesFound 2 primes in the 2018 Tour de Primes Mountain Stage2019 Tour de Primes highest prime countFound 22 primes in the 2019 Tour de Primes2020 Tour de Primes highest prime scoreFound 21 primes in the 2020 Tour de PrimesFound 4 mega primes in the 2020 Tour de PrimesFound 8 primes in the 2021 Tour de PrimesFound 1 mega prime in the 2021 Tour de Primes321 LLR Double Silver: Earned 200,000,000 credits (201,403,028)Cullen LLR Double Silver: Earned 200,000,000 credits (201,409,561)ESP LLR Double Silver: Earned 200,000,000 credits (214,825,147)Generalized Cullen/Woodall LLR Double Bronze: Earned 100,000,000 credits (133,750,194)PPS LLR Double Gold: Earned 500,000,000 credits (735,628,070)PSP LLR Double Bronze: Earned 100,000,000 credits (181,223,975)SoB LLR Double Silver: Earned 200,000,000 credits (207,028,068)SR5 LLR Double Silver: Earned 200,000,000 credits (214,437,634)SGS LLR Double Silver: Earned 200,000,000 credits (205,718,935)TPS LLR (retired) Silver: Earned 100,000 credits (235,439)TRP LLR Double Silver: Earned 200,000,000 credits (201,215,056)Woodall LLR Double Silver: Earned 200,000,000 credits (201,651,344)321 Sieve (suspended) Double Silver: Earned 200,000,000 credits (235,451,253)Cullen/Woodall Sieve (suspended) Emerald: Earned 50,000,000 credits (83,794,448)Generalized Cullen/Woodall Sieve (suspended) Double Silver: Earned 200,000,000 credits (285,139,652)PPS Sieve Double Ruby: Earned 2,000,000,000 credits (2,731,606,455)Sierpinski (ESP/PSP/SoB) Sieve (suspended) Double Silver: Earned 200,000,000 credits (203,523,358)TRP Sieve (suspended) Double Silver: Earned 200,000,000 credits (201,489,157)AP 26/27 Double Silver: Earned 200,000,000 credits (442,961,701)GFN Double Ruby: Earned 2,000,000,000 credits (2,148,298,569)WW Double Ruby: Earned 2,000,000,000 credits (2,469,152,000)PSA Double Silver: Earned 200,000,000 credits (259,058,048)
Message 142752 - Posted: 28 Aug 2020 | 12:15:03 UTC - in response to Message 142742.

I don't have an OpenCL card, but would certainly be willing to get one if it would help in development.


Unless you have a very old GPU, almost any modern NVidia or AMD GPU will run OpenCL applications with the correct driver installed.

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321 LLR Ruby: Earned 2,000,000 credits (2,092,823)Cullen LLR Ruby: Earned 2,000,000 credits (2,289,208)ESP LLR Amethyst: Earned 1,000,000 credits (1,445,099)Generalized Cullen/Woodall LLR Ruby: Earned 2,000,000 credits (2,180,764)PPS LLR Amethyst: Earned 1,000,000 credits (1,225,852)PSP LLR Ruby: Earned 2,000,000 credits (2,064,832)SoB LLR Amethyst: Earned 1,000,000 credits (1,669,219)SR5 LLR Ruby: Earned 2,000,000 credits (2,065,004)SGS LLR Amethyst: Earned 1,000,000 credits (1,412,461)TRP LLR Ruby: Earned 2,000,000 credits (2,089,856)Woodall LLR Ruby: Earned 2,000,000 credits (2,112,258)321 Sieve (suspended) Ruby: Earned 2,000,000 credits (2,107,153)PPS Sieve Turquoise: Earned 5,000,000 credits (5,096,952)AP 26/27 Turquoise: Earned 5,000,000 credits (5,150,782)GFN Turquoise: Earned 5,000,000 credits (7,510,843)WW Double Silver: Earned 200,000,000 credits (243,048,000)PSA Amethyst: Earned 1,000,000 credits (1,022,470)
Message 142758 - Posted: 28 Aug 2020 | 17:00:52 UTC - in response to Message 142748.

Sorry if this is a stupid question, but it means proth20 uses OpenCL to prove primality of Proth numbers? So my plan to buy a 1650 and do both sieving and primality proof of Proth numbers with it, would work?

If so, why isn't proth20 used on PG? Or is CPU still faster and GPUs are generally better used for GFN instead of Proth?

Unless you have a very old GPU, almost any modern NVidia or AMD GPU will run OpenCL applications with the correct driver installed.
One is embedded Intel, the other had some older Radeon card that I think doesn't support OpenCL, but I'd have to check next week when I have access to the physical computer.
____________
1281979 * 2^485014 + 1 is prime ... no further hits up to: n = 4,800,000

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The "Shut up already!" badge:  This loud mouth has mansplained on the forums over 10 thousand times!  Sheesh!!!Discovered the World's First GFN-19 prime!!!Discovered 1 mega primeFound 1 prime in the 2018 Tour de PrimesFound 1 prime in the 2019 Tour de PrimesFound 1 prime in the 2020 Tour de PrimesFound 2 primes in the 2021 Tour de Primes321 LLR Turquoise: Earned 5,000,000 credits (5,132,712)Cullen LLR Turquoise: Earned 5,000,000 credits (5,038,114)ESP LLR Turquoise: Earned 5,000,000 credits (6,177,890)Generalized Cullen/Woodall LLR Ruby: Earned 2,000,000 credits (2,500,221)PPS LLR Sapphire: Earned 20,000,000 credits (20,751,038)PSP LLR Turquoise: Earned 5,000,000 credits (7,956,186)SoB LLR Sapphire: Earned 20,000,000 credits (36,067,618)SR5 LLR Jade: Earned 10,000,000 credits (10,007,110)SGS LLR Ruby: Earned 2,000,000 credits (3,718,606)TRP LLR Turquoise: Earned 5,000,000 credits (5,084,329)Woodall LLR Turquoise: Earned 5,000,000 credits (5,032,821)321 Sieve (suspended) Jade: Earned 10,000,000 credits (10,061,196)Cullen/Woodall Sieve (suspended) Ruby: Earned 2,000,000 credits (4,170,256)Generalized Cullen/Woodall Sieve (suspended) Turquoise: Earned 5,000,000 credits (5,059,304)PPS Sieve Sapphire: Earned 20,000,000 credits (22,885,121)Sierpinski (ESP/PSP/SoB) Sieve (suspended) Amethyst: Earned 1,000,000 credits (1,035,522)TRP Sieve (suspended) Ruby: Earned 2,000,000 credits (2,051,121)AP 26/27 Jade: Earned 10,000,000 credits (10,118,303)GFN Emerald: Earned 50,000,000 credits (78,031,938)WW Sapphire: Earned 20,000,000 credits (32,204,000)PSA Jade: Earned 10,000,000 credits (12,445,029)
Message 142762 - Posted: 28 Aug 2020 | 18:45:00 UTC - in response to Message 142758.

If so, why isn't proth20 used on PG? Or is CPU still faster and GPUs are generally better used for GFN instead of Proth?


It's new. We can only do so much, and things take time.
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Credit: 284,558,019
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321 LLR Ruby: Earned 2,000,000 credits (2,092,823)Cullen LLR Ruby: Earned 2,000,000 credits (2,289,208)ESP LLR Amethyst: Earned 1,000,000 credits (1,445,099)Generalized Cullen/Woodall LLR Ruby: Earned 2,000,000 credits (2,180,764)PPS LLR Amethyst: Earned 1,000,000 credits (1,225,852)PSP LLR Ruby: Earned 2,000,000 credits (2,064,832)SoB LLR Amethyst: Earned 1,000,000 credits (1,669,219)SR5 LLR Ruby: Earned 2,000,000 credits (2,065,004)SGS LLR Amethyst: Earned 1,000,000 credits (1,412,461)TRP LLR Ruby: Earned 2,000,000 credits (2,089,856)Woodall LLR Ruby: Earned 2,000,000 credits (2,112,258)321 Sieve (suspended) Ruby: Earned 2,000,000 credits (2,107,153)PPS Sieve Turquoise: Earned 5,000,000 credits (5,096,952)AP 26/27 Turquoise: Earned 5,000,000 credits (5,150,782)GFN Turquoise: Earned 5,000,000 credits (7,510,843)WW Double Silver: Earned 200,000,000 credits (243,048,000)PSA Amethyst: Earned 1,000,000 credits (1,022,470)
Message 142775 - Posted: 29 Aug 2020 | 6:57:26 UTC - in response to Message 142762.

It's new. We can only do so much, and things take time.
I didn't mean that as accusation why it takes so long. ;) I was rather wondering if there's a hidden catch.

I think I'll buy a 1650 then to try how it works out, also then I'll finally be able to efficiently collect AP, PPS SV and GFN badges. :)

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1281979 * 2^485014 + 1 is prime ... no further hits up to: n = 4,800,000

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