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Message boards : Number crunching : A Prime Chinese New Year Challenge

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Michael Gutierrez
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Message 159335 - Posted: 16 Jan 2023 | 4:50:54 UTC

Welcome to A Prime Chinese New Year Challenge

The first challenge of the 2023 Series will be a 3-day challenge on the PPS-MEGA and GFN-17 MEGA applications, beginning 22 January 12:00 UTC and ending 25 January 12:00 UTC.

Welcome to 2023! And just 7 days away, on Jan. 22, in the Lunar Chinese calendar: the year 4721. What do you know, a prime number! Here's what the Prime Numbers Fandom Wiki has to say about this number:

4,721 is a prime number between 4,001 and 7,000. 4,721 has 2 factors, 1 and 4,721. It is the ??th prime number, and the ??th prime number between 3,001 and 4,000. Cardinal Number: Unknown Ordinal Number: Unknown Roman Numeral: Unknown Factorization: 4721 Standard Form: 4,721 x 10^3 Proofs: ✅ — 4,721 can be divided by 1 ❌ — 4,721 cannot be divided by 2-4,720 ✅ — 4,721 can be divided by 4,721

Who knew that the Roman Numerals of some numbers are still unknown 🤯 It seems there are still many profound mysteries to uncover about the year 4721! What a time to be alive!

To participate in the challenge:

• Wait until the challenge timeframe starts (or set your BOINC Client download schedule accordingly), as tasks issued before the challenge will not count.
• In your PrimeGrid preferences section, select only the Proth Mega Prime Search (LLR) and Generalized Fermat Prime Search n=17 projects.

Important reminders:

• Note on LLR2 tasks: LLR2 has eliminated the need for a full doublecheck task on each workunit, but has replaced it with a short verification task. Expect to receive a few tasks about 1% of normal length.
• The typical deadline for some of these WUs is longer than the challenge time-frame, so make sure your computer is able to return the WUs within 3 days. Only tasks issued AFTER the start time and returned BEFORE the finish time will be counted.
• 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. Thanks!

• Windows: 32 bit, 64 bit
• Linux: 32 bit, 64 bit
• Mac: 64 bit
• Multi-threading is not recommended for PPS-MEGA.
• Uses fast proof tasks so no double check tasks are needed. Everyone is "first"!

Intel and recent AMD CPUs with FMA3 capabilities (Haswell or better for Intel, Zen-2 or better for AMD) will have a very large advantage running LLR tasks, and CPUs with AVX-512 capabilities (certain recent Intel Skylake-X and Xeon CPUs, AMD Ryzen 7000 and EPYC CPUs) will be the fastest.

Note that LLR is running the latest AVX-512 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, especially if they're highly overclocked. If you have certain recent Intel Skylake-X, Xeon, or AMD Zen-4+ CPUs, especially if it's overclocked or has overclocked memory, and haven't run the new AVX-512 LLR before, we strongly suggest running it before the challenge while you are monitoring the temperatures.

• Windows: CPU x86, x64. GPU¹: Nvidia, AMD, Intel ARC.
• Linux: CPU: x86, x64, ARM64. GPU¹: Nvidia, AMD, Intel ARC.
• Mac: CPU: x64, ARM64. GPU¹: Nvidia, AMD, Apple M-Series.
• All GFN use fast proof tasks so no double check tasks are needed. Everyone is "first"!

¹ OpenCL 1.1 or higher is required.

GFN-17 MEGA WU's are currently averaging 35 minutes on CPU and 3 minutes on GPU.
For a general idea of how your GPU stacks up, you can have a look at the fastest GPUs list.

As with all number crunching, excessive heat can potentially cause permanent hardware failure. Please ensure your cooling system is sufficient. Please see this post for more details on how you can "stress test" your CPU, and please see this post for tips on running GFN on your GPU successfully.
IMPORTANT: Overclocking -- including factory overclocking -- on Nvidia GPUs is very strongly discouraged. Even if your GPU can run other tasks without difficulty, it may be unable to run GFN tasks when overclocked.

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 22 January 12:00 UTC and received BEFORE 25 January 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.

The Proth Prime Search is done in collaboration with the Proth Search project. This search looks for primes in the form of 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.

Our initial 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=800K. PG 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 about 275 "classical" Fermat number factors known. Current primes found in PPS definitely make it into the Top 5000 Primes database.

Once the 800K goal is reached, we may head to 1M before turning our focus to smaller k values and higher n values. For example, k < 300 complete to n = 2M, k < 600 complete to n=1.5M and so on.

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 have never been tested. For 2010, we hope to complete our reservation to 800K and extend it to 1M.

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:

What is LLR2?

LLR2 is an improvement to the LLR application developed by our very own Pavel Atnashev and stream. It utilizes Gerbicz checks to enable the Fast DoubleCheck feature, which will nearly double the speed of PrimeGrid's progress on the projects it's applied to. For more information, see this forum post.
____________

Time flies like an arrow. Fruit flies like a banana.

gemini8

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Message 159336 - Posted: 16 Jan 2023 | 6:46:57 UTC - in response to Message 159335.

4,721 is a prime number between 3,001 and 4,000.

I see:
3001 < 4721 < 4000.
Erm...

____________
Greetings, Jens

1461*2^3373383+1

Crun-chi
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Message 159339 - Posted: 16 Jan 2023 | 7:52:28 UTC - in response to Message 159335.

This is old and incorrect info...
____________
92*10^1439761-1 NEAR-REPDIGIT PRIME :) :) :)
4 * 650^498101-1 CRUS PRIME
2022202116^131072+1 GENERALIZED FERMAT
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Message 159348 - Posted: 16 Jan 2023 | 14:53:18 UTC

Surely it's MMMMDCCXXI.

Ken_g6
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Message 159350 - Posted: 16 Jan 2023 | 17:14:27 UTC - in response to Message 159348.

Surely it's MMMMDCCXXI.

Nope. Wikipedia says:

The largest number that can be represented in this notation is 3,999 (MMMCMXCIX)

During the centuries that Roman numerals remained the standard way of writing numbers throughout Europe, there were various extensions to the system designed to indicate larger numbers, none of which were ever standardised.

But perhaps it could be |CD|DCCXXI

Grebuloner
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Message 159351 - Posted: 16 Jan 2023 | 17:53:21 UTC - in response to Message 159339.

This is old and incorrect info...

More...confusing. It really comes down to the individual CPU's cache structure. For CPUs with less than 2MB L3/core (or L2+L3 for newer Ryzen/Intel), multithreading (2 threads/task) is the way to go, and the rest can just run a single thread.

We can certainly agree that it's time to give the opening spiel a good update. The AVX-512 section now needs to add Ryzen 7000/Epic Genoa. Great little performers despite needing 2 clocks per instruction.
____________
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composite
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Message 159352 - Posted: 16 Jan 2023 | 19:34:43 UTC - in response to Message 159350.

Surely it's MMMMDCCXXI.

Nope. Wikipedia says:

The largest number that can be represented in this notation is 3,999 (MMMCMXCIX)

During the centuries that Roman numerals remained the standard way of writing numbers throughout Europe, there were various extensions to the system designed to indicate larger numbers, none of which were ever standardised.

But perhaps it could be |CD|DCCXXI

There's a Y4K problem in Roman Numerals because there hasn't been a letter selected for 5K.
The American film industry should just abandon this obsolete junk.

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Message 159353 - Posted: 16 Jan 2023 | 20:04:27 UTC

4721 is the 636th prime.

The previous prime is 4703 (distance 18).

The next prime is 4723 (distance 2, twins!).

The factorization of 4721 - 1 is 2^4 * 5 * 59. The order of 2 mod 4721 is odd, namely 5 * 59.

The expression 4721*2^n + 1 is prime for n = 9, 47, 63, 155, 471, 479, 1163, 1403, 3453, 3719, 6867, 7419, 7797, ...

And 4721*2^n - 1 is prime for n = 6, 14, 18, 34, 54, 146, 278, 342, 426, 3218, 5330, ...

The Mersenne number 2^4721 - 1 is composite, but no factors have been found.

/JeppeSN

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Message 159354 - Posted: 16 Jan 2023 | 20:34:04 UTC - in response to Message 159353.

4721 is the 636th prime.

The previous prime is 4703 (distance 18).

The next prime is 4723 (distance 2, twins!).

The factorization of 4721 - 1 is 2^4 * 5 * 59. The order of 2 mod 4721 is odd, namely 5 * 59.

The expression 4721*2^n + 1 is prime for n = 9, 47, 63, 155, 471, 479, 1163, 1403, 3453, 3719, 6867, 7419, 7797, ...

And 4721*2^n - 1 is prime for n = 6, 14, 18, 34, 54, 146, 278, 342, 426, 3218, 5330, ...

The Mersenne number 2^4721 - 1 is composite, but no factors have been found.

/JeppeSN

Are there any values of n in common between primes 4721*2^n + 1 and 4721*2^n - 1 or are the n's always distinct?

Michael Gutierrez
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Message 159355 - Posted: 16 Jan 2023 | 20:37:32 UTC

I'd actually never heard of the Y4K problem, that's hilarious lmao

Also it seems someone has updated the Prime Numbers Fandom Wiki since yesterday -- to everyone's relief, I'm sure, it turns out that 4721 > 4000 after all.

The other issues are fixed too lol, thanks for pointing those out
____________

Time flies like an arrow. Fruit flies like a banana.

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Message 159356 - Posted: 16 Jan 2023 | 20:41:20 UTC - in response to Message 159352.

The American film industry should just abandon this obsolete junk.

It's a global issue, not just America.

JeppeSN

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Message 159370 - Posted: 17 Jan 2023 | 17:28:07 UTC - in response to Message 159354.

Are there any values of n in common between primes 4721*2^n + 1 and 4721*2^n - 1 or are the n's always distinct?

You see an even/odd pattern?

It is because taken modulo 3, the expression 4721*2^n ± 1 is congruent to (-1)*(-1)^n ± 1. So if n is even, 3 divides the Proth candidate. And if n is odd, 3 divides the other candidate. Since n will be either even or odd, divisibility by 3 will always spoil your hope.

For k that are multiples of 3, there is hope.

/JeppeSN

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Message 159374 - Posted: 17 Jan 2023 | 18:03:54 UTC - in response to Message 159370.

Are there any values of n in common between primes 4721*2^n + 1 and 4721*2^n - 1 or are the n's always distinct?

You see an even/odd pattern?

It is because taken modulo 3, the expression 4721*2^n ± 1 is congruent to (-1)*(-1)^n ± 1. So if n is even, 3 divides the Proth candidate. And if n is odd, 3 divides the other candidate. Since n will be either even or odd, divisibility by 3 will always spoil your hope.

For k that are multiples of 3, there is hope.

/JeppeSN

I see. For example the pair of candidates with k=15 and n=2 are the twin primes 59 and 61.

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Message 159396 - Posted: 18 Jan 2023 | 23:32:32 UTC - in response to Message 159374.

I see. For example the pair of candidates with k=15 and n=2 are the twin primes 59 and 61.

And for k=33, there is 33*2^22 ± 1.

Edit: It is not too hard to find better examples, including 177*2^1032 ± 1 and 291*2^1553 ± 1. In fact, many of the top twins are constructed from base 2.

/JeppeSN

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Message 159397 - Posted: 19 Jan 2023 | 4:23:24 UTC - in response to Message 159396.

I see. For example the pair of candidates with k=15 and n=2 are the twin primes 59 and 61.

And for k=33, there is 33*2^22 ± 1.

Edit: It is not too hard to find better examples, including 177*2^1032 ± 1 and 291*2^1553 ± 1. In fact, many of the top twins are constructed from base 2.

/JeppeSN

Actually, show me ANY twin primes of the form k*b^n ± 1 where k is not divisible by 3 except when b is divisible by 3. There are none and it MUST be that way. Just restating what you said earlier.

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Message 159424 - Posted: 19 Jan 2023 | 14:30:42 UTC

Doing some pre-testing on GFN-17. Seeing following on CPU tasks:

Warning: b > 125,000,000: the test may fail.

Anything to be worried about? No problems on the handful of units I've run so far.

"b" currently around 126.7M and obviously increasing as time goes on.

Yves Gallot
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Message 159428 - Posted: 19 Jan 2023 | 15:43:16 UTC - in response to Message 159424.

Doing some pre-testing on GFN-17. Seeing following on CPU tasks:
Warning: b > 125,000,000: the test may fail.
Anything to be worried about? No problems on the handful of units I've run so far.

At b = 125M, genefer is starting to compute and print the round-off error. On your computer, it is <= 0.375 (it is ~ 0.4 without fma).
The real limit where some CPU errors are going to be reported should be greater than 140M. For the moment, it is just monitoring.

30k tasks completed each day => b += 228,000 each day.
If 3 * 10 * 30k ~ 1M tasks are completed during the challenge then the leading edge will be 127.4M + 7.6M ~ 135M.

A new version of the code (that is already used for GFN-16, see https://www.primegrid.com/forum_thread.php?id=10090) will be deployed to extend the search limit but since it is 20% slower it should be done as late as possible. That is not needed for the challenge but maybe before TdP.

Michael Millerick
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Message 159430 - Posted: 19 Jan 2023 | 16:43:45 UTC - in response to Message 159428.

A new version of the code (that is already used for GFN-16, see https://www.primegrid.com/forum_thread.php?id=10090) will be deployed to extend the search limit but since it is 20% slower it should be done as late as possible. That is not needed for the challenge but maybe before TdP.

Is it only the CPU version that is slower, or will the GPU version also be slower as a result?
____________

Yves Gallot
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Message 159431 - Posted: 19 Jan 2023 | 16:50:06 UTC - in response to Message 159430.

Is it only the CPU version that is slower, or will the GPU version also be slower as a result?

The GPU version is the same. Only the CPU version will be updated.

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Message 159494 - Posted: 21 Jan 2023 | 18:04:16 UTC

Should there not be less than 6 hours on the clock? I thought midnight to midnight? Or is it really Noon to Noon?
____________
My lucky numbers are 121*2^4553899-1 and 3756801695685*2^666669±1
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Michael Goetz
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Message 159497 - Posted: 21 Jan 2023 | 18:30:03 UTC - in response to Message 159494.

Should there not be less than 6 hours on the clock? I thought midnight to midnight? Or is it really Noon to Noon?

The schedule originally had only dates, but no times, so they originally all said 00:00 (midnight).

The times have been assigned and the schedule reflects the actual start/end times, which for this challenge is 12:00 UTC. Noon is correct.
____________
My lucky number is 75898524288+1

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Message 159502 - Posted: 21 Jan 2023 | 20:53:16 UTC

We are past the solar term Dàhán, and at the time of posting this (20:53 UTC, that is January 22 at 04:53 in China's time zone) the astronomical New Moon occurs. This mean that this day (January 22 after western calendar) is the first day of the new year. Welcome to the year of the Bunny (rabbit or hare). More specifically the Water Bunny (see sexagenary cycle).

Gōng xǐ fā cái! May the year bring you prime numbers!

/JeppeSN

PS! New Moon is also an opportunity to watch comet C/2022 E3 (unless you are far south of the equator).

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Message 159508 - Posted: 22 Jan 2023 | 4:15:30 UTC - in response to Message 159351.

More...confusing. It really comes down to the individual CPU's cache structure. For CPUs with less than 2MB L3/core (or L2+L3 for newer Ryzen/Intel), multithreading (2 threads/task) is the way to go, and the rest can just run a single thread.

We can certainly agree that it's time to give the opening spiel a good update. The AVX-512 section now needs to add Ryzen 7000/Epic Genoa. Great little performers despite needing 2 clocks per instruction.

Interesting.
I have Ryzen 5900X and 3900X and a couple of Xeons 26xx v2 and 26xx v3
In your opinion is it better to run multithreading tasks? HT is on everywhere if it matters.
Thank you!
____________

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Message 159509 - Posted: 22 Jan 2023 | 4:24:01 UTC - in response to Message 159508.

More...confusing. It really comes down to the individual CPU's cache structure. For CPUs with less than 2MB L3/core (or L2+L3 for newer Ryzen/Intel), multithreading (2 threads/task) is the way to go, and the rest can just run a single thread.

We can certainly agree that it's time to give the opening spiel a good update. The AVX-512 section now needs to add Ryzen 7000/Epic Genoa. Great little performers despite needing 2 clocks per instruction.

Interesting.
I have Ryzen 5900X and 3900X and a couple of Xeons 26xx v2 and 26xx v3
In your opinion is it better to run multithreading tasks? HT is on everywhere if it matters.
Thank you!

All of your CPUs have a ton of cache and are fast enough for the challenge, so 1 thread/task is what you'll want to use. Make sure you have settings in BOINC to use at most 50% of your CPUs as the extra logical cores provided by HT/SMT are no good for LLR.
____________
Eating more cheese on Thursdays.

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Message 159510 - Posted: 22 Jan 2023 | 5:01:24 UTC - in response to Message 159509.

All of your CPUs have a ton of cache and are fast enough for the challenge, so 1 thread/task is what you'll want to use. Make sure you have settings in BOINC to use at most 50% of your CPUs as the extra logical cores provided by HT/SMT are no good for LLR.

Is it better to check GFN-17 or PPS-MEGA for CPUs for max output during the challenge?
____________

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Message 159517 - Posted: 22 Jan 2023 | 11:59:30 UTC

I could plead for divine intervention - but nothing will save me from cranking up all CPUs and GPUs in this heat.
May I not be fully roasted.

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Message 159522 - Posted: 22 Jan 2023 | 13:33:37 UTC

Somehow, someway the database lags way behind or is even frozen.

At the 45 min-mark I had 3 GFN17Mega and none PPSMEGA-results uploaded. All stats were right by then.

Now I'm having multiple more results of both types uploaded but no advances in my result pages as well as in the race pages.

Hmmm.

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Message 159523 - Posted: 22 Jan 2023 | 13:34:57 UTC - in response to Message 159522.

Somehow, someway the database lags way behind or is even frozen.

At the 45 min-mark I had 3 GFN17Mega and none PPSMEGA-Tasks uploaded. All stats were right by then.

Now I'm having multiple more tasks of both types uploaded but no advances in my result pages as well as in the race pages.

Hmmm.

Same at my side... WU is processed m upload and download but not appear on my account page or on challenge stat

____________
92*10^1439761-1 NEAR-REPDIGIT PRIME :) :) :)
4 * 650^498101-1 CRUS PRIME
2022202116^131072+1 GENERALIZED FERMAT
Proud member of team Aggie The Pew. Go Aggie!

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Message 159525 - Posted: 22 Jan 2023 | 14:21:54 UTC

Dave

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Message 159528 - Posted: 22 Jan 2023 | 15:59:06 UTC

Magic happened. Officially.

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Message 159542 - Posted: 23 Jan 2023 | 1:48:13 UTC

Ni!

Michael Gutierrez
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Message 159545 - Posted: 23 Jan 2023 | 6:07:23 UTC

Challenge: A Prime Chinese New Year
App: 21 (PPS-MEGA)
Fast DC tasks are NOT included.
(As of 2023-01-23 05:36:04 UTC)

107704 tasks have been sent out. [CPU/GPU/anonymous_platform: 107704 (100%) / 0 (0%) / 0 (0%)]

Of those tasks that have been sent out:

9165 (9%) were aborted. [9165 (9%) / 0 (0%) / 0 (0%)]
173 (0%) came back with some kind of an error. [173 (0%) / 0 (0%) / 0 (0%)]
65212 (61%) have returned a successful result. [65215 (61%) / 0 (0%) / 0 (0%)]
33167 (31%) are still in progress. [33165 (31%) / 0 (0%) / 0 (0%)]

Of the tasks that have been returned successfully:

14865 (23%) are pending validation. [14868 (23%) / 0 (0%) / 0 (0%)]
50347 (77%) have been successfully validated. [50347 (77%) / 0 (0%) / 0 (0%)]
0 (0%) were invalid. [0 (0%) / 0 (0%) / 0 (0%)]
0 (0%) are inconclusive. [0 (0%) / 0 (0%) / 0 (0%)]

The current leading edge (i.e., latest work unit for which work has actually been sent out to a host) is n=3446391. The leading edge was at n=3445599 at the beginning of the challenge. Since the challenge started, the leading edge has advanced 0.02% as much as it had prior to the challenge!

Challenge: A Prime Chinese New Year
App: 25 (GFN-17-MEGA)
Fast DC tasks are NOT included.
(As of 2023-01-23 05:36:20 UTC)

373831 tasks have been sent out. [CPU/GPU/anonymous_platform: 116351 (31%) / 256015 (68%) / 1465 (0%)]

Of those tasks that have been sent out:

16210 (4%) were aborted. [4636 (1%) / 11574 (3%) / 0 (0%)]
816 (0%) came back with some kind of an error. [30 (0%) / 786 (0%) / 0 (0%)]
217874 (58%) have returned a successful result. [60228 (16%) / 157663 (42%) / 1 (0%)]
138998 (37%) are still in progress. [51480 (14%) / 86052 (23%) / 1464 (0%)]

Of the tasks that have been returned successfully:

142354 (65%) are pending validation. [38005 (17%) / 104367 (48%) / 0 (0%)]
75520 (35%) have been successfully validated. [22223 (10%) / 53296 (24%) / 1 (0%)]
0 (0%) were invalid. [0 (0%) / 0 (0%) / 0 (0%)]
0 (0%) are inconclusive. [0 (0%) / 0 (0%) / 0 (0%)]

The current leading edge (i.e., latest work unit for which work has actually been sent out to a host) is b=130904638. The leading edge was at b=128203838 at the beginning of the challenge. Since the challenge started, the leading edge has advanced 3.15% as much as it had prior to the challenge!
____________

Time flies like an arrow. Fruit flies like a banana.

Conan

Joined: 24 Mar 09
Posts: 236
ID: 37336
Credit: 56,053,831
RAC: 30,849

Message 159548 - Posted: 23 Jan 2023 | 8:50:33 UTC

Just curious as I have not seen this posted (probably didn't look hard enough) but what are the Fast DC tasks that are not included in this challenge?

Is it the really short running tasks that prove the main task?

So I have done dozens of these and they don't count towards the challenge but are added to my score.

Conan
____________

E-30 [Black Sheep]

Joined: 30 Dec 05
Posts: 2
ID: 2007
Credit: 153,752,131
RAC: 116,507

Message 159549 - Posted: 23 Jan 2023 | 9:02:50 UTC

hi from seti usa
____________

gemini8

Joined: 2 Jan 16
Posts: 115
ID: 434794
Credit: 411,430,919
RAC: 250,518

Message 159550 - Posted: 23 Jan 2023 | 9:43:18 UTC - in response to Message 159548.

Just curious as I have not seen this posted (probably didn't look hard enough) but what are the Fast DC tasks that are not included in this challenge?

Is it the really short running tasks that prove the main task?

So I have done dozens of these and they don't count towards the challenge but are added to my score.

The Fast DC tasks are the really short running tasks that prove the main tasks, and - tadaa! - they also count towards the challenge.
____________
Greetings, Jens

1461*2^3373383+1

Vato
Volunteer tester

Joined: 2 Feb 08
Posts: 838
ID: 18447
Credit: 612,587,868
RAC: 186,076

Message 159551 - Posted: 23 Jan 2023 | 10:24:07 UTC - in response to Message 159550.

yes - fast DC tasks get credit that counts towards the challenge,
but the stats posted above about progress do NOT include fast DC tasks
____________

Michael Gutierrez
Volunteer moderator
Project scientist

Joined: 21 Mar 17
Posts: 333
ID: 764476
Credit: 46,281,510
RAC: 0

Message 159574 - Posted: 24 Jan 2023 | 5:43:51 UTC

Challenge: A Prime Chinese New Year
App: 21 (PPS-MEGA)
Fast DC tasks are NOT included.
(As of 2023-01-24 05:35:57 UTC)

226940 tasks have been sent out. [CPU/GPU/anonymous_platform: 226940 (100%) / 0 (0%) / 0 (0%)]

Of those tasks that have been sent out:

10347 (5%) were aborted. [10347 (5%) / 0 (0%) / 0 (0%)]
659 (0%) came back with some kind of an error. [659 (0%) / 0 (0%) / 0 (0%)]
181519 (80%) have returned a successful result. [181542 (80%) / 0 (0%) / 0 (0%)]
34457 (15%) are still in progress. [34459 (15%) / 0 (0%) / 0 (0%)]

Of the tasks that have been returned successfully:

21700 (12%) are pending validation. [21723 (12%) / 0 (0%) / 0 (0%)]
159819 (88%) have been successfully validated. [159819 (88%) / 0 (0%) / 0 (0%)]
0 (0%) were invalid. [0 (0%) / 0 (0%) / 0 (0%)]
0 (0%) are inconclusive. [0 (0%) / 0 (0%) / 0 (0%)]

The current leading edge (i.e., latest work unit for which work has actually been sent out to a host) is n=3447344. The leading edge was at n=3445599 at the beginning of the challenge. Since the challenge started, the leading edge has advanced 0.05% as much as it had prior to the challenge!

Challenge: A Prime Chinese New Year
App: 25 (GFN-17-MEGA)
Fast DC tasks are NOT included.
(As of 2023-01-24 05:37:00 UTC)

722157 tasks have been sent out. [CPU/GPU/anonymous_platform: 219377 (30%) / 501315 (69%) / 1465 (0%)]

Of those tasks that have been sent out:

20197 (3%) were aborted. [5138 (1%) / 15059 (2%) / 0 (0%)]
1954 (0%) came back with some kind of an error. [98 (0%) / 1857 (0%) / 0 (0%)]
558257 (77%) have returned a successful result. [159784 (22%) / 398545 (55%) / 1 (0%)]
141826 (20%) are still in progress. [54403 (8%) / 85946 (12%) / 1464 (0%)]

Of the tasks that have been returned successfully:

292030 (52%) are pending validation. [78838 (14%) / 213265 (38%) / 0 (0%)]
266227 (48%) have been successfully validated. [80946 (14%) / 185280 (33%) / 1 (0%)]
1 (0%) were invalid. [1 (0%) / 0 (0%) / 0 (0%)]
0 (0%) are inconclusive. [0 (0%) / 0 (0%) / 0 (0%)]

The current leading edge (i.e., latest work unit for which work has actually been sent out to a host) is b=133511520. The leading edge was at b=128203838 at the beginning of the challenge. Since the challenge started, the leading edge has advanced 6.20% as much as it had prior to the challenge!
____________

Time flies like an arrow. Fruit flies like a banana.

JeppeSN

Joined: 5 Apr 14
Posts: 1777
ID: 306875
Credit: 48,041,408
RAC: 13,641

Message 159591 - Posted: 24 Jan 2023 | 17:41:11 UTC

If you check the person at the bottom of https://www.primegrid.com/challenge/2023_1/top_users.html, that is usually going to be someone with zero main tasks and only short proof tasks. The fact that they are still on that list and have credit shows that proof tasks do count.

/JeppeSN

Conan

Joined: 24 Mar 09
Posts: 236
ID: 37336
Credit: 56,053,831
RAC: 30,849

Message 159599 - Posted: 24 Jan 2023 | 22:21:11 UTC

I can see that crashtech and tng are really trading blows at the top of the list, who is going to win I wonder?

Conan

____________

bcavnaugh

Joined: 8 Nov 13
Posts: 275
ID: 273570
Credit: 1,226,049,354
RAC: 1,494,040

Message 159610 - Posted: 25 Jan 2023 | 4:35:40 UTC - in response to Message 159591.

If you check the person at the bottom of https://www.primegrid.com/challenge/2023_1/top_users.html, that is usually going to be someone with zero main tasks and only short proof tasks. The fact that they are still on that list and have credit shows that proof tasks do count.

/JeppeSN

I never understood how some Members never get Prof Tasks and only get Main Tasks.
I would love to see crashtech Hosts.

Michael Millerick
Volunteer tester

Joined: 4 Feb 09
Posts: 917
ID: 35074
Credit: 770,642,544
RAC: 919,501

Message 159611 - Posted: 25 Jan 2023 | 4:57:20 UTC

There are tons of tasks in progress. I hope that no one is planning for a large last minute dump of task uploads to the server. That could prove to be problematic.
____________

Nick

Joined: 11 Jul 11
Posts: 2139
ID: 105020
Credit: 8,002,627,942
RAC: 2,557,168

Message 159612 - Posted: 25 Jan 2023 | 8:24:14 UTC - in response to Message 159611.

There are tons of tasks in progress. I hope that no one is planning for a large last minute dump of task uploads to the server. That could prove to be problematic.

I have many downloaded tasks as I worry that I will lose my internet connection and not notice for a while.
There was a planned outage at midnight on Tuesday (AEDT time) for maintenance, which did happen.
I return all my tasks when they are finished - internet connection being OK.
I will be aborting about 1500 tasks at the end of the challenge as I forgot to change settings at the right time.

Conan

Joined: 24 Mar 09
Posts: 236
ID: 37336
Credit: 56,053,831
RAC: 30,849

Message 159613 - Posted: 25 Jan 2023 | 8:55:54 UTC - in response to Message 159612.

There are tons of tasks in progress. I hope that no one is planning for a large last minute dump of task uploads to the server. That could prove to be problematic.

I have many downloaded tasks as I worry that I will lose my internet connection and not notice for a while.
There was a planned outage at midnight on Tuesday (AEDT time) for maintenance, which did happen.
I return all my tasks when they are finished - internet connection being OK.
I will be aborting about 1500 tasks at the end of the challenge as I forgot to change settings at the right time.

I wont bother to dump any tasks, I will just lower my Resource share and let them complete when Boinc gets round to it.

I was still running other tasks as well as PrimeGrid as I got caught out by a big download just before the start of the challenge, so I upped the resource share of PrimeGrid to 5000 which virtually made everything else just stop till the challenge was over, bar a few work units with deadlines to meet.

When I drop the resource share back to 150-200 PrimeGrid might sit there for a few weeks before it downloads any more work.

Conan
____________

Nick

Joined: 11 Jul 11
Posts: 2139
ID: 105020
Credit: 8,002,627,942
RAC: 2,557,168

Message 159617 - Posted: 25 Jan 2023 | 11:14:31 UTC - in response to Message 159612.

I will be aborting about 1500 tasks at the end of the challenge as I forgot to change settings at the right time.

My bad - I was only looking at Mega.
I will be aborting between 3000 and 3500 tasks.

Hans Sveen

Joined: 18 Aug 05
Posts: 46
ID: 423
Credit: 1,676,980,128
RAC: 961,736

Message 159623 - Posted: 25 Jan 2023 | 12:04:47 UTC

Hello!
And we are done, Thank You !
See some of You(all?) in a week (tdP)😍

Hans S.
____________
MyStats

vaughan

Joined: 11 Aug 05
Posts: 314
ID: 224
Credit: 10,087,724,501
RAC: 3,000,846

Message 159625 - Posted: 25 Jan 2023 | 12:36:36 UTC

As always thank you to the Admins for keeping the server alive for a great challenge.
____________

Dirk Sellsted

Joined: 15 Feb 17
Posts: 179
ID: 492091
Credit: 196,085,976
RAC: 593,025

Message 159631 - Posted: 25 Jan 2023 | 16:37:30 UTC

⚠️ You can help PrimeGrid server: stop testing Mega and GFN-17 and don't test GFN-16. You can check large numbers and some projects with DC. It will help to empty the 382k "LLR2 certificate jobs pending" more quickly.

Stolen from the discord server. I've moved onto TRP and PSP and larger than 17 GFN's.

Nick

Joined: 11 Jul 11
Posts: 2139
ID: 105020
Credit: 8,002,627,942
RAC: 2,557,168

Message 159633 - Posted: 25 Jan 2023 | 16:49:02 UTC

What happened at the end of this challenge is that I increased from 500 to 1000 cloud cores, then 1500, then 2000.
I really hoped I would achieve super powers with 1000 cores.
Maybe I did - with the perfect overtake in the last 15 minutes?

JeppeSN

Joined: 5 Apr 14
Posts: 1777
ID: 306875
Credit: 48,041,408
RAC: 13,641

Message 159635 - Posted: 25 Jan 2023 | 17:27:04 UTC - in response to Message 159613.

When I drop the resource share back to 150-200 PrimeGrid might sit there for a few weeks before it downloads any more work.

Tasks that do not trickle may time out after 4 days (you can still get credit, but there is no saying whether the task will be duplicated and sent to some other user which may then finish before you). Tasks that trickle will have deadlines extended. /JeppeSN

Eudy Silva

Joined: 26 Aug 17
Posts: 2018
ID: 918937
Credit: 571,523,935
RAC: 190,071

Message 159639 - Posted: 25 Jan 2023 | 17:50:31 UTC

Almost 2 million tasks in the challenge !
____________

"Accidit in puncto, quod non contingit in anno."
Something that does not occur in a year may, perchance, happen in a moment.

Scott Brown
Volunteer moderator
Volunteer tester
Project scientist

Joined: 17 Oct 05
Posts: 2349
ID: 1178
Credit: 17,518,847,246
RAC: 4,068,801

Message 159640 - Posted: 25 Jan 2023 | 18:53:44 UTC - in response to Message 159633.

What happened at the end of this challenge is that I increased from 500 to 1000 cloud cores, then 1500, then 2000.
I really hoped I would achieve super powers with 1000 cores.
Maybe I did - with the perfect overtake in the last 15 minutes?

Congratulations on the overtake.

I was busy not looking at pending primes (that process thrashes the server drives heavily) and not adding in any spikes to the struggling server load over a short time period.

bcavnaugh

Joined: 8 Nov 13
Posts: 275
ID: 273570
Credit: 1,226,049,354
RAC: 1,494,040

Message 159642 - Posted: 25 Jan 2023 | 20:36:52 UTC - in response to Message 159599.

I can see that crashtech and tng are really trading blows at the top of the list, who is going to win I wonder?

Conan

I wonder who has more Host?
Even if most are Cloud based.
I still would like to see an event that only allows 10-12 hosts Max and no cloud.

Chooka

Joined: 15 May 18
Posts: 282
ID: 1014486
Credit: 738,330,656
RAC: 338,781

Message 159644 - Posted: 25 Jan 2023 | 20:46:01 UTC - in response to Message 159642.

It's all about the cloud these days by the looks bc.
Whoever throws the most money at it, wins. Some things don't change with BOINC :)

TdP will be the same.
____________

Слава Україні!

Nick

Joined: 11 Jul 11
Posts: 2139
ID: 105020
Credit: 8,002,627,942
RAC: 2,557,168

Message 159645 - Posted: 25 Jan 2023 | 21:06:02 UTC - in response to Message 159640.

What happened at the end of this challenge is that I increased from 500 to 1000 cloud cores, then 1500, then 2000.
I really hoped I would achieve super powers with 1000 cores.
Maybe I did - with the perfect overtake in the last 15 minutes?

Congratulations on the overtake.

I was busy not looking at pending primes (that process thrashes the server drives heavily) and not adding in any spikes to the struggling server load over a short time period.

Cheers Scott,

I had no idea what could have happened as I made this push too late to make sense.
It was ridiculously close.

I will attempt to be more predictable, but the cloud computing is enticing!

pschoefer
Volunteer developer
Volunteer tester

Joined: 20 Sep 05
Posts: 677
ID: 845
Credit: 2,858,608,858
RAC: 256,593

Message 159648 - Posted: 25 Jan 2023 | 21:45:37 UTC - in response to Message 159428.

Doing some pre-testing on GFN-17. Seeing following on CPU tasks:
Warning: b > 125,000,000: the test may fail.
Anything to be worried about? No problems on the handful of units I've run so far.

At b = 125M, genefer is starting to compute and print the round-off error. On your computer, it is <= 0.375 (it is ~ 0.4 without fma).
The real limit where some CPU errors are going to be reported should be greater than 140M. For the moment, it is just monitoring.

It looks like there are a few unlucky numbers at b<140M. During the challenge, I had two tasks ending with "validation failed!": b=135028388 using avx and b=136030622 using sse4. In both cases, I was able to reproduce this on a different computer with avx, while fma produced a good result, so I'm quite confident that it's the b limit and not some random hardware error.
____________

bcavnaugh

Joined: 8 Nov 13
Posts: 275
ID: 273570
Credit: 1,226,049,354
RAC: 1,494,040

Message 159649 - Posted: 25 Jan 2023 | 22:30:32 UTC - in response to Message 159644.

It's all about the cloud these days by the looks bc.
Whoever throws the most money at it, wins. Some things don't change with BOINC :)

TdP will be the same.

Yea!, but it takes all the fun out of all the events here and in general BOINC altogether.

Yves Gallot
Volunteer developer
Project scientist

Joined: 19 Aug 12
Posts: 772
ID: 164101
Credit: 305,388,375
RAC: 3,091

Message 159651 - Posted: 25 Jan 2023 | 22:41:32 UTC - in response to Message 159648.

It looks like there are a few unlucky numbers at b<140M. During the challenge, I had two tasks ending with "validation failed!": b=135028388 using avx and b=136030622 using sse4. In both cases, I was able to reproduce this on a different computer with avx, while fma produced a good result, so I'm quite confident that it's the b limit and not some random hardware error.

Yes, I am supervising avx/sse4 implementations and the round-off error is most often 0.4375. Then few tasks may fail. I am testing the new version and the code will be updated before TdP.

vaughan

Joined: 11 Aug 05
Posts: 314
ID: 224
Credit: 10,087,724,501
RAC: 3,000,846

Message 159653 - Posted: 25 Jan 2023 | 23:26:21 UTC

Nice overtake Nick - well timed deployment of resources.

Unfortunately I left my advance just a few minutes late yielding #7 by just a few points.

It was a fun challenge. Thanks to Rytis and TSC to allow this to happen.
____________

Nick

Joined: 11 Jul 11
Posts: 2139
ID: 105020
Credit: 8,002,627,942
RAC: 2,557,168

Message 159656 - Posted: 25 Jan 2023 | 23:57:27 UTC - in response to Message 159653.

Nice overtake Nick - well timed deployment of resources.

Unfortunately I left my advance just a few minutes late yielding #7 by just a few points.

It was a fun challenge. Thanks to Rytis and TSC to allow this to happen.

Cheers Vaughan,
And thankyou to Rytis too - hopefully I won't surprise you like that again.

Chooka

Joined: 15 May 18
Posts: 282
ID: 1014486
Credit: 738,330,656
RAC: 338,781

Message 159659 - Posted: 26 Jan 2023 | 10:05:49 UTC - in response to Message 159649.

Yes bcavnaugh, we are both in agreeance on that.
That's why I don't get hung up on these "challenges" They are just a bit of fun for me.

Goodluck in the TdP.
Must look up when that's due to start.
____________

Слава Україні!

Nick

Joined: 11 Jul 11
Posts: 2139
ID: 105020
Credit: 8,002,627,942
RAC: 2,557,168

Message 159661 - Posted: 26 Jan 2023 | 11:45:38 UTC - in response to Message 159659.

Goodluck in the TdP.
Must look up when that's due to start.

The day before Groundhog day?
Edit: I think I know what you mean - what day and time here in Australia?
I think we get to have a go at February for 11 hours before PG - but QLD is 10 hours?
Another edit: I am leaving out 2 or 3 time zones. SA 10.5 hours. Not sure about NT. WA 9 hours. I may be incorrect

Dave

Joined: 13 Feb 12
Posts: 3144
ID: 130544
Credit: 2,210,534,956
RAC: 149,594

Message 159668 - Posted: 26 Jan 2023 | 12:30:11 UTC - in response to Message 159659.

Must look up when that's due to start.

Usual time it always starts, Feb 1 @ 00:00:00UT.

We have to make sure the servers are stable first.

Michael Goetz
Volunteer moderator

Joined: 21 Jan 10
Posts: 13870
ID: 53948
Credit: 382,872,983
RAC: 108,893

Message 159675 - Posted: 26 Jan 2023 | 15:00:11 UTC - in response to Message 159644.

It's all about the cloud these days by the looks bc.
Whoever throws the most money at it, wins. Some things don't change with BOINC :)

TdP will be the same.

This is definitely true -- but it was true before the cloud too. He with the most money buys the fastest computers and the most computers, regardless of whether they are owned or rented.

If anything, the cloud probably helps the little guys with fewer dollars. It's one thing to build a bunch of HEPCs with \$999 CPUs and \$1500 GPUs. That's a sizeable investment for most. But lots of people can throw \$100 or so at a challenge.

There's probably a thesis or two in this discussion; it's certainly a complicated topic. But it's definitely not as simple as "the cloud is the root of all evil" or "the cloud is the greatest thing since sliced bread".

What I do know is that with my meager computers, and my meager budget, I can do better in challenges now than I could before the cloud was a thing. Or worse. It's my choice whether to spend or not. But that's a choice I didn't have before; always buying bleeding edge kit wasn't an option for me.

Overall, my view as one of the "little guys" is that it's a good thing. I have choice now. I like that.

As an admin, it's crystal clear, however: it drives participation way, way up.
____________
My lucky number is 75898524288+1

Conan

Joined: 24 Mar 09
Posts: 236
ID: 37336
Credit: 56,053,831
RAC: 30,849

Message 159679 - Posted: 26 Jan 2023 | 22:12:46 UTC

Is there a dedicated thread on this Tour de Primes thing? I did a couple of searches on these forums and found nothing about it.

Conan
____________

Eudy Silva

Joined: 26 Aug 17
Posts: 2018
ID: 918937
Credit: 571,523,935
RAC: 190,071

Message 159682 - Posted: 27 Jan 2023 | 0:29:55 UTC - in response to Message 159679.

Is there a dedicated thread on this Tour de Primes thing? I did a couple of searches on these forums and found nothing about it.

Conan

Right hand side, by the clock.
____________

"Accidit in puncto, quod non contingit in anno."
Something that does not occur in a year may, perchance, happen in a moment.

Conan

Joined: 24 Mar 09
Posts: 236
ID: 37336
Credit: 56,053,831
RAC: 30,849

Message 159683 - Posted: 27 Jan 2023 | 1:00:36 UTC - in response to Message 159682.

Is there a dedicated thread on this Tour de Primes thing? I did a couple of searches on these forums and found nothing about it.

Conan

Right hand side, by the clock.

Thank you, that link has just been added today, at least I can see what it is all about.

Conan
____________

Message boards : Number crunching : A Prime Chinese New Year Challenge