PrimeGrid
Please visit donation page to help the project cover running costs for this month

Toggle Menu

Join PrimeGrid

Returning Participants

Community

Leader Boards

Results

Other

drummers-lowrise

Advanced search

Message boards : Proth Prime Search : What does "Factors found: 4 (avg. 4/task") mean?

Author Message
Profile KyleProject donor
Send message
Joined: 1 Jun 14
Posts: 42
ID: 315843
Credit: 3,159,436
RAC: 1,406
321 LLR Bronze: Earned 10,000 credits (48,756)Cullen LLR Bronze: Earned 10,000 credits (20,704)ESP LLR Bronze: Earned 10,000 credits (43,542)Generalized Cullen/Woodall LLR Bronze: Earned 10,000 credits (74,656)PPS LLR Silver: Earned 100,000 credits (203,920)PSP LLR Bronze: Earned 10,000 credits (27,208)SoB LLR Bronze: Earned 10,000 credits (60,097)SR5 LLR Bronze: Earned 10,000 credits (51,260)SGS LLR Bronze: Earned 10,000 credits (22,511)TRP LLR Bronze: Earned 10,000 credits (53,040)Woodall LLR Bronze: Earned 10,000 credits (77,612)PPS Sieve Gold: Earned 500,000 credits (680,942)AP 26/27 Silver: Earned 100,000 credits (105,118)GFN Amethyst: Earned 1,000,000 credits (1,631,750)PSA Bronze: Earned 10,000 credits (41,191)
Message 96808 - Posted: 13 Jul 2016 | 14:01:54 UTC

What does "Factors found" mean? Thank you.

Profile Michael GoetzProject donor
Volunteer moderator
Project administrator
Project scientist
Avatar
Send message
Joined: 21 Jan 10
Posts: 13013
ID: 53948
Credit: 199,689,421
RAC: 215,882
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 Primes321 LLR Ruby: Earned 2,000,000 credits (2,810,011)Cullen LLR Ruby: Earned 2,000,000 credits (2,005,249)ESP LLR Turquoise: Earned 5,000,000 credits (5,009,577)Generalized Cullen/Woodall LLR Ruby: Earned 2,000,000 credits (2,145,754)PPS LLR Turquoise: Earned 5,000,000 credits (7,719,659)PSP LLR Ruby: Earned 2,000,000 credits (4,591,521)SoB LLR Sapphire: Earned 20,000,000 credits (34,221,148)SR5 LLR Turquoise: Earned 5,000,000 credits (8,293,415)SGS LLR Ruby: Earned 2,000,000 credits (2,014,138)TRP LLR Ruby: Earned 2,000,000 credits (2,737,347)Woodall LLR Ruby: Earned 2,000,000 credits (2,195,123)321 Sieve Turquoise: Earned 5,000,000 credits (5,055,870)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 (20,110,788)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 (10,114,260)GFN Emerald: Earned 50,000,000 credits (65,947,938)PSA Jade: Earned 10,000,000 credits (12,404,447)
Message 96809 - Posted: 13 Jul 2016 | 14:27:49 UTC - in response to Message 96808.

What does "Factors found" mean? Thank you.


The process of searching for prime numbers starts with a large set of candidates. The status of each individual candidate (number) is initially unknown. It's either prime, or more likely, it's composite, but we don't know which.

Testing each individual number takes a long time, so we use a more efficient strategy: We first run a sieve, which rapidly is able to establish that many of the candidates are composite. Once we know a candidate is composite, we're done with it and don't need to consider it anymore.

Once we're done with the sieve, we're left with a much smaller set of candidates whose status is unknown. We then test this smaller set, one candidate at a time, with a program such as LLR or Genefer to determine its final status as prime or composite. (Genefer actually tests for a candidate being a "probable prime", but that's not relevant to this discussion.)

Now, back to your question. When the sieve proves that a candidate is composite, it does so by finding a factor of that candidate, i.e., it finds a small prime number that divides the candidate. The statistics showing number of factors found is therefore indicating how many candidates your sieve tasks have proven to be composite.

(And, in case your next question is "How can I see my factors?", you can't. We don't store that information. The number of factors found at the beginning of a sieve is prohibitively huge, and storing a record of who found what is impractical.)
____________
Please do not PM me with support questions. Ask on the forums instead. Thank you!

My lucky number is 75898524288+1

Profile KyleProject donor
Send message
Joined: 1 Jun 14
Posts: 42
ID: 315843
Credit: 3,159,436
RAC: 1,406
321 LLR Bronze: Earned 10,000 credits (48,756)Cullen LLR Bronze: Earned 10,000 credits (20,704)ESP LLR Bronze: Earned 10,000 credits (43,542)Generalized Cullen/Woodall LLR Bronze: Earned 10,000 credits (74,656)PPS LLR Silver: Earned 100,000 credits (203,920)PSP LLR Bronze: Earned 10,000 credits (27,208)SoB LLR Bronze: Earned 10,000 credits (60,097)SR5 LLR Bronze: Earned 10,000 credits (51,260)SGS LLR Bronze: Earned 10,000 credits (22,511)TRP LLR Bronze: Earned 10,000 credits (53,040)Woodall LLR Bronze: Earned 10,000 credits (77,612)PPS Sieve Gold: Earned 500,000 credits (680,942)AP 26/27 Silver: Earned 100,000 credits (105,118)GFN Amethyst: Earned 1,000,000 credits (1,631,750)PSA Bronze: Earned 10,000 credits (41,191)
Message 96830 - Posted: 14 Jul 2016 | 14:16:48 UTC - in response to Message 96809.

Thank you!

Message boards : Proth Prime Search : What does "Factors found: 4 (avg. 4/task") mean?

[Return to PrimeGrid main page]
DNS Powered by DNSEXIT.COM
Copyright © 2005 - 2019 Rytis Slatkevičius (contact) and PrimeGrid community. Server load 4.30, 3.94, 3.40
Generated 12 Nov 2019 | 9:21:15 UTC