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Message boards : Number crunching : Leonids Shower Challenge

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Joined: 27 Nov 11
Posts: 1041
ID: 120786
Credit: 253,127,948
RAC: 46,183
Found 1 prime in the 2018 Tour de Primes321 LLR Amethyst: Earned 1,000,000 credits (1,654,329)Cullen LLR Amethyst: Earned 1,000,000 credits (1,305,599)ESP LLR Ruby: Earned 2,000,000 credits (2,085,950)Generalized Cullen/Woodall LLR Ruby: Earned 2,000,000 credits (2,050,279)PPS LLR Ruby: Earned 2,000,000 credits (2,149,793)PSP LLR Ruby: Earned 2,000,000 credits (2,420,512)SoB LLR Amethyst: Earned 1,000,000 credits (1,493,571)SR5 LLR Ruby: Earned 2,000,000 credits (2,238,295)SGS LLR Ruby: Earned 2,000,000 credits (2,038,730)TRP LLR Ruby: Earned 2,000,000 credits (2,066,087)Woodall LLR Amethyst: Earned 1,000,000 credits (1,293,758)Cullen/Woodall Sieve (suspended) Silver: Earned 100,000 credits (207,387)Generalized Cullen/Woodall Sieve Turquoise: Earned 5,000,000 credits (5,047,512)PPS Sieve Double Bronze: Earned 100,000,000 credits (100,422,123)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 (55,079,605)PSA Sapphire: Earned 20,000,000 credits (43,298,465)
Message 122203 - Posted: 7 Nov 2018 | 12:35:16 UTC
Last modified: 8 Nov 2018 | 8:33:58 UTC

Welcome to the Leonids Shower Challenge

The Leonids is an average shower, producing up to 15 meteors per hour at its peak. This shower is unique in that it has a cyclonic peak about every 33 years where hundreds of meteors per hour can be seen. That last of these occurred in 2001. The Leonids is produced by dust grains left behind by comet Tempel-Tuttle, which was discovered in 1865. The shower runs annually from November 6-30. It peaks this year on the night of the 17th and morning of the 18th. The waxing gibbous moon will set shortly after midnight leaving fairly dark skies for what could be a good early morning show. Best viewing will be from a dark location after midnight. Meteors will radiate from the constellation Leo, but can appear anywhere in the sky.

Arithmetic progressions
In mathematics, an arithmetic progression (AP) or arithmetic sequence is a sequence of numbers such that the difference between the consecutive terms is constant. For instance, the sequence 5, 7, 9, 11, 13, 15 … is an arithmetic progression with common difference of 2.

An arithmetic progression of primes is a sequence of primes with a common difference between any two successive numbers in the sequence. For example 3, 7, 11 is an arithmetic progression of 3 primes with a common difference of 4.

For an arithmetic progression (AP) of primes, AP-k is k primes of the form p + d*n for some d (the common difference between the primes) and k consecutive values of n. The above AP-3 is 3 + 4*n for n=0,1,2.

How to Participate?
To participate in the Challenge, please select only the AP 27 (AP27) project in your PrimeGrid preferences section. The challenge will begin 17th November 2018 12:00 UTC and end 20th November 2018 12:00 UTC. Application builds are available for Linux , Windows and MacIntel CPUs and GPUs. CPU apps are only available for 64 bit CPUs. High end Nvidia GPUs will have a very large advantage.

Tasks will take ~29 hours on average for CPUs and ~75 minutes on average for GPUs. If your computer is highly overclocked, please consider "stress testing" it. If you haven't run the AP app before, we strongly suggest running it before the challenge while you are monitoring the temperatures. You don't want to turn your machine into a meteor!

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 to the left of the countdown clock.

Scoring Information

Scores will be kept for individuals and teams. Only tasks issued AFTER 17 November 2018 12:00 UTC and received BEFORE 20 November 2018 12:00 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 a 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. :)

For more information about the AP27 search, please visit these links:
- AP 27 Search
- AP 26 Search
- Jens Kruse Andersen's Primes in Arithmetic Progression Records

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Message boards : Number crunching : Leonids Shower Challenge

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