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Message boards : Number crunching : Solar Eclipse Challenge

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Found 1 prime in the 2018 Tour de Primes321 LLR Amethyst: Earned 1,000,000 credits (1,318,504)Cullen LLR Amethyst: Earned 1,000,000 credits (1,040,598)ESP LLR Amethyst: Earned 1,000,000 credits (1,295,496)Generalized Cullen/Woodall LLR Amethyst: Earned 1,000,000 credits (1,679,162)PPS LLR Ruby: Earned 2,000,000 credits (2,017,456)PSP LLR Ruby: Earned 2,000,000 credits (2,420,512)SoB LLR Amethyst: Earned 1,000,000 credits (1,448,977)SR5 LLR Ruby: Earned 2,000,000 credits (2,216,000)SGS LLR Ruby: Earned 2,000,000 credits (2,011,030)TRP LLR Ruby: Earned 2,000,000 credits (2,062,053)Woodall LLR Amethyst: Earned 1,000,000 credits (1,059,108)Cullen/Woodall Sieve (suspended) Silver: Earned 100,000 credits (207,387)Generalized Cullen/Woodall Sieve Ruby: Earned 2,000,000 credits (2,881,320)PPS Sieve Emerald: Earned 50,000,000 credits (88,613,510)Sierpinski (ESP/PSP/SoB) Sieve (suspended) Ruby: Earned 2,000,000 credits (3,227,972)TRP Sieve (suspended) Turquoise: Earned 5,000,000 credits (5,021,659)AP 26/27 Sapphire: Earned 20,000,000 credits (20,033,065)GFN Emerald: Earned 50,000,000 credits (52,931,783)PSA Sapphire: Earned 20,000,000 credits (43,298,465)
Message 119491 - Posted: 19 Jul 2018 | 14:30:55 UTC
Last modified: 20 Jul 2018 | 14:42:41 UTC

Welcome to the Solar Eclipse Challenge

The fifth Challenge of the 2018 Challenge series is a 3 day challenge to celebrate the Solar Eclipse on August 11th. The challenge is being offered on the Proth Prime Search (LLR) Project.

A solar eclipse occurs when the disk of the moon appears to cross in front of the disk of the sun. A total solar eclipse — like the one that took place on Aug. 21, 2017 — occurs when the disk of the moon blocks 100 percent of the solar disk. A partial eclipse occurs when the moon covers only part of the sun.

The Aug. 11, 2018 partial solar eclipse will touch many countries in the Northern Hemisphere. This animation shows the path of the moon's shadow.

The eclipse will start out over the North Atlantic Ocean and Greenland, moving north and east so that the shadow simultaneously moves toward Iceland, northern Europe and the northern polar regions. Continuing its path over the top of the planet, the shadow will be wide enough to cover most of northern Russia from east to west. It will then dip down into Mongolia, China and surrounding areas.

It will officially begin when the moon first appears to make contact with the sun's disk at 4:02 a.m. EDT (0802 UTC). Maximum eclipse will happen at 5:46 a.m. EDT (0946 UTC), when the eclipse is at magnitude 0.7361.

To participate in the Challenge, please select only the Proth Prime Search LLR (PPS) project in your PrimeGrid preferences section. The challenge will begin 10th August 2018 18:00 UTC and end 13th August 2018 18:00 UTC. Note that PPSE and PPS Mega do not count towards this challenge.

Application builds are available for Linux 32 and 64 bit, Windows 32 and 64 bit and MacIntel. Intel CPUs with AVX capabilities (Sandy Bridge, Ivy Bridge, Haswell, Broadwell, Skylake, Kaby Lake, Coffee Lake) will have a very large advantage, and Intel CPUs with FMA3 (Haswell, Broadwell, Skylake, Kaby Lake, Coffee Lake) will be the fastest.

ATTENTION: The primality program LLR is CPU intensive; so, it is vital to have a stable system with good cooling. It does not tolerate "even the slightest of errors." Please see this post for more details on how you can "stress test" your computer. Tasks on one CPU core will take ~30mins on fast/newer computers and 2+ hours on slower/older computers. If your computer is highly overclocked, please consider "stress testing" it. Sieving is an excellent alternative for computers that are not able to LLR. :)

Highly overclocked Haswell, Broadwell, Skylake, Kaby Lake or Coffee Lake (i.e., Intel Core i7, i5, and i3 -4xxx or better) computers running the application will see fastest times. Note that SR5 is running the latest FMA3 version of LLR which takes full advantage of the features of these newer CPUs. It's faster than the previous LLR app and draws more power and produces more heat. If you have a Haswell, Broadwell, Skylake, Kaby Lake or Coffee Lake CPU, especially if it's overclocked or has overclocked memory, and haven't run the new FMA3 LLR before, we strongly suggest running it before the challenge while you are monitoring the temperatures.

Please, please, please make sure your machines are up to the task.

Time zone converter:

The World Clock - Time Zone Converter

NOTE: The countdown clock on the front page uses the host computer time. Therefore, if your computer time is off, so will the countdown clock. For precise timing, use the UTC Time in the data section at the very top, above the countdown clock.

Scoring Information

Scores will be kept for individuals and teams. Only tasks issued AFTER 10th August 2018 18:00 UTC and received BEFORE 13th August 2018 18:00 UTC will be considered for credit. We will be using the same scoring method as we currently use for BOINC credits. A quorum of 2 is NOT needed to award Challenge score - i.e. no double checker. Therefore, each returned result will earn a Challenge score. Please note that if the result is eventually declared invalid, the score will be removed.

At the Conclusion of the Challenge

    We kindly ask users "moving on" to ABORT their tasks instead of DETACHING, RESETTING, or PAUSING.

    ABORTING tasks allows them to be recycled immediately; thus a much faster "clean up" to the end of an LLR Challenge. DETACHING, RESETTING, and PAUSING tasks causes them to remain in limbo until they EXPIRE. Therefore, we must wait until tasks expire to send them out to be completed.

    Please consider either completing what's in the queue or ABORTING them. Thank you. :)

About the Proth Prime Search

The Proth Prime Search is done in collaboration with the Proth Search project. This search looks for primes in the form k*2^n+1. With the condition 2^n > k, these are often called Proth primes. This project also has the added bonus of possibly finding factors of "classical" Fermat numbers or Generalized Fermat numbers. As this requires PrimeFormGW (PFGW) (a primality-testing program), once PrimeGrid finds a prime, it is then tested on PrimeGrid's servers for divisibility.

Proth Search only searches for k<1200. PrimeGrid created an extension to that which includes all candidates 1200<k<10000 for n<5M. It is this extension which we call PPSE.

Initially, PrimeGrid's PPS project's goal was to double check all previous work up to n=500K for odd k<1200 and to fill in any gaps that were missed. We have accomplished that now and have increased it to n=3M. PG's LLRNet searched up to n=200,000 and found several missed primes in previously searched ranges. Although primes that small did not make it into the Top 5000 Primes database, the work was still important as it may have led to new factors for "classical" Fermat numbers or Generalized Fermat numbers. While there are many GFN factors, currently there are only 297 "classical" Fermat number factors known. Current primes found in PPS definitely make it into the Top 5000 Primes database.

For more information about "Proth" primes, please visit these links:

About Proth Search

The Proth Search project was established in 1998 by Ray Ballinger and Wilfrid Keller to coordinate a distributed effort to find Proth primes (primes of the form k*2^n+1) for k < 300. Ray was interested in finding primes while Wilfrid was interested in finding divisors of Fermat number. Since that time it has expanded to include k < 1200. Mark Rodenkirch (aka rogue) has been helping Ray keep the website up to date for the past few years.

Early in 2008, PrimeGrid and Proth Search teamed up to provide a software managed distributed effort to the search. Although it might appear that PrimeGrid is duplicating some of the Proth Search effort by re-doing some ranges, few ranges on Proth Search were ever double-checked. This has resulted in PrimeGrid finding primes that were missed by previous searchers. By the end of 2008, all new primes found by PrimeGrid were eligible for inclusion in Chris Caldwell's Prime Pages Top 5000. Sometime in 2009, over 90% of the tests handed out by PrimeGrid were numbers that had never been tested.

PrimeGrid intends to continue the search indefinitely for Proth primes.

What is LLR?

The Lucas-Lehmer-Riesel (LLR) test is a primality test for numbers of the form N = k*2^n − 1, with 2^n > k. Also, LLR is a program developed by Jean Penne that can run the LLR-tests. It includes the Proth test to perform +1 tests and PRP to test non base 2 numbers. See also:

(Edouard Lucas: 1842-1891, Derrick H. Lehmer: 1905-1991, Hans Riesel: 1929-2014).

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Joined: 5 Apr 14
Posts: 680
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Credit: 8,447,024
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321 LLR Bronze: Earned 10,000 credits (48,835)ESP LLR Bronze: Earned 10,000 credits (13,226)PPS LLR Gold: Earned 500,000 credits (606,650)SoB LLR Silver: Earned 100,000 credits (132,293)SR5 LLR Bronze: Earned 10,000 credits (16,010)TRP LLR Bronze: Earned 10,000 credits (14,746)PSA Turquoise: Earned 5,000,000 credits (7,614,290)
Message 119497 - Posted: 19 Jul 2018 | 21:33:59 UTC

Solar eclipses can occur at new moon only. Note that we have eclipses at consecutive new moons this time since 2018-Jul-13 was an eclipse as well (Wikipedia). /JeppeSN

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Message boards : Number crunching : Solar Eclipse Challenge

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