News archive

Part 3 of the 10^21 search has started
Part 2 of the 10²¹ search will be finished, for the most part, today. There are still ~2000 unfinished WUs which can take up to a couple of weeks to complete, depending on individual participants processing them.

Part 3 of the search will look for amicable pairs where the smaller member of the pair has its largest prime factor between 10¹¹ and 10¹⁴:

m=m1*p, 10¹¹ < p < 10¹⁴

There are too many primes larger than 10¹⁴ (all primes up to 5*10¹⁹ need to be checked), so they will require a different approach and a new application when the time comes.

Most of the participants have already started getting part 3 WUs. The new work units will require ~2.5-2.7 GB RAM on CPU, and the same amount of RAM on GPU (for GPU applications), so the minimum requirement for GPUs will be 3 GB RAM.

Update April 9th, 2024: I found a bug in OpenCL applications, which resulted in many false negatives (around 12.5%). The bug was in the new code that I added for the part 3, so the previous search is unaffected. Version 3.09 has this bug fixed, but I had to restart the part 3. Luckily, we were only a couple of weeks in.
27 Mar 2024, 10:24:42 UTC · Discuss

Beta test of part 3 of the 10^21 search
Part 2 of the 10^21 search will be over some time in March this year, so it's time to start getting ready for part 3! I found a few bugs in the current GPU applications that needed to be fixed (CPU applications are fine).

To make sure everything works as intended, I will launch a small beta-test of the part 3 search by the end of this week. The new work units will require ~2.5-2.7 GB RAM on CPU, and the same amount of RAM on GPU (for GPU applications), so the minimum requirement for GPUs will be 3 GB RAM.

The purpose of the test is to confirm that all OS/CPU/GPU combinations work properly and confirm that 3 GB GPUs can process the new work units.
22 Jan 2024, 20:15:18 UTC · Discuss

The search up to 10^21
The search up to 10²¹ has started! Over 50,000 new amicable pairs have been found in the first few days.

Due to the huge size of search space, first stage of the search will only look for all amicable pairs where smaller number is of the form 3^N*...*p where N > 0 and p < 10¹¹. I expect that this will find 2-3 million new amicable pairs in a year or so.

Note that system memory requirements are higher now because all prime numbers < 10¹¹ need to be stored in memory for the search.
25 Oct 2019, 13:11:37 UTC · Discuss

GPU version bugfix release
GPU versions for all platforms were updated to fix "Error -58" computation error when resuming stopped task.
8 Apr 2019, 11:00:47 UTC · Discuss

Power outage
The server was down today between 11:04 and 14:20 (CEST) because of a major power outage in Hetzner datacenter. Everything should be up and running again now.
24 May 2018, 12:41:34 UTC · Discuss

GPU version fix
There was a serious bug in GPU version: https://github.com/SChernykh/Amicable/commit/3470ed855d244100f37b0b7ab4c912d2b9365a93
Unfortunately, it skipped some numbers in an unpredictable way for "large primes" work units for the last ~~20 days~~ 9 days. I'll have to reissue all such work units to cover everything missed. The GPU versions for all platforms are already updated.

Sorry for the mess, but it's good that the bug is fixed relatively early, because it was hard to notice.
27 Mar 2018, 17:45:25 UTC · Discuss

MacOS GPU version released
GPU requirements are the same as for Windows and Linux versions: AMD (HD 5xxx or newer) or NVIDIA (GTX 4xx or newer) GPU with OpenCL support and at least 2 GB of video memory.

The MacOS GPU version has been confirmed to work on OS X El Capitan and MacOS Sierra. Older MacOS versions have poor OpenCL support and may fail to run the GPU version.
16 Sep 2017, 8:24:36 UTC · Discuss

The search up to 2^64 is complete!
Congratulations to everyone who took part in this search!

- There are 2,390,655 amicable pairs with smaller member below 2^64 in total
- BOINC volunteers found 552,874 new amicable pairs below 2^64

A more detailed analysis of amicable pairs distribution will follow later this month. And don't forget to edit your preferences and check that you're all set up to run the current search up to 10^20.
16 Aug 2017, 7:26:12 UTC · Discuss

Credits for the old application (search up to 2^64) doubled
It's sad to see everyone leave the old (and unfinished) application "Amicable Numbers up to 2^64" so I decided to double credit points for it.

Everyone can switch their CPUs back to gain some more credits.

Note that you can run "Amicable Numbers up to 2^64" on CPU and "Amicable Numbers up to 10^20" on GPU on the same PC at the same time!

Here's what you need to set in project preferences:
Use CPU, AMD/ATI GPU, NVIDIA GPU = yes
Run application 2^64 = yes
Run application 10^20 = no
Accept work from other applications = yes

With these settings your CPU will get tasks (and more credits in general) from "2^64" only, and your GPU will get tasks from "10^20" thanks to "Accept work from other applications = yes" selected.
3 Jul 2017, 16:09:14 UTC · Discuss

The search up to 10^20
It will be started tomorrow (July 1st)!

I've decided to speed up the launch of the next search due to performance issues with GPU version that everyone experiences now.

What will happen on July 1st:

1) "Amicable Numbers up to 10^20" application will start receiving tasks.
2) All GPU versions for the old application "Amicable Numbers up to 2^64" will be deprecated.
3) Credit points for both applications will be re-balanced to make sure that RAC doesn't change.

So all GPUs should automatically switch to the new application, and the old application will remain as CPU-only until it finishes.
30 Jun 2017, 16:11:33 UTC · Discuss

New application for double checking current search
I've launched a new application called Amicable Numbers up to 2^64 (double check). It will re-run some of past work units.

If you don't want to run WUs which were already done before, you can deselect this application on the preferences page: https://sech.me/boinc/Amicable/prefs.php?subset=project

NOTE: If you are unable to achieve 100% GPU load (to maximize RAC) with work units from the main application, I recommend to switch to this new application: it will have GPU-friendly work units.
16 Jun 2017, 14:27:55 UTC · Discuss

Finish line of the current search and next steps
Hello all crunchers!

The search for amicable numbers up to 2^64 is almost done: all previously known numbers are already covered by the search, zero numbers were missed which is very good and gives me confidence. It's extremely unlikely to find anything in the remaining WUs, but they need to be processed to complete the search.

The next steps will be:

1) Double check a small portion of the search space to increase confidence that nothing is missed. It will be a separate application so everyone will have choice whether to move to the next search range or help verify the current range.
2) Start the search for amicable numbers up to 10^20. It will be a separate application as well and it will become the default application as soon as the current search runs out of WUs. CPU version is ready, GPU version is work in progress and hopefully will be finished before the start of the search.
8 Jun 2017, 10:19:57 UTC · Discuss

Credit badges for 100, 200 and 500 thousand total credit
There are new entry level badges on the project: white hollow stars for 100, 200, 500 thousand total credit.

14 Apr 2017, 13:07:16 UTC · Discuss

Credit badges
I've added credit badges. The first badge is given for 1,000,000 total credit, the last badge is given for 1,000,000,000 total credit. I chose 1 million as an entry level because there are already 258 users above that value and their contribution is 97.2% of project's total credit. So if you've been active on the project, you should already have one of these badges.

Bronze stars: 1, 2, 5 million total credit
Silver stars: 10, 20, 50 million total credit
Gold stars: 100, 200, 500 million total credit
Big gold star: 1 billion total credit

8 Apr 2017, 10:59:54 UTC · Discuss

MacOS X 64-bit application released
It's in beta test now. Discussion is here: https://sech.me/boinc/Amicable/forum_thread.php?id=58
2 Apr 2017, 15:32:20 UTC · Discuss

Credit per WU is doubled temporarily
It appears that current work units are 2 times slower on average, so I've set credit per WU to 3236.07 temporarily (2 times more than usual). This is until the project reaches 50%, when a whole new type of WU will start, so I'll revise credit per WU once again then.
28 Mar 2017, 5:14:01 UTC · Discuss

GPU version 1.12 bug
This version had a bug, so I had to cancel all work which was in progress for this version and then reissue all work units which were processed with this version only, i.e. all work units that have two results with GPU version 1.12 in "completed and validated" state. 16433 work units have been reissued, it's approximately 1 day of calculations.

The project is back to using version 1.11 for now. I'll release a proper fixed version later today.
22 Mar 2017, 10:53:19 UTC · Discuss

Update on project progress and badges
227,482 amicable pairs have been found so far, ~340,000 are yet to be found according to my estimations. Due to the way this search is organized and how amicable numbers are distributed, I expect almost all of those ~340k pairs to be found before the search reaches 50% in a couple of weeks, and only a few thousand of new pairs will be found after 50%. So if your target is to get some of the discoverer badges, now is the time to crunch with everything you've got.

Since there will be only a few new pairs after 50%, this is when I'll introduce credit badges.

UPDATE 2017-03-26: ~250,000 amicable pairs will be found in the next few days. Don't miss the opportunity!
17 Mar 2017, 9:44:22 UTC · Discuss

Gridcoin
The project is now included in the list of projects that give rewards on the Gridcoin Network: https://gridcoinstats.eu/projects.php

Happy crunching all Gridcoin users!
12 Mar 2017, 20:14:20 UTC · Discuss

Project status update
After the recent fix for the very short work units issue I had to regenerate remaining work units using the new code. Of course there are fewer work units left now because they are not "very short" anymore, and the server status page says that ETA for current goal is June 18th, 2017. This is correct and it means that the next goal will be to find all amicable numbers < 10^20 and it will start in the summer. 10^20 is ~5.42 times larger than 2^64 and the new application will be slower because it will have to deal with numbers that don't fit in 64 bits. So the next goal will take 8-10 times more time.
8 Mar 2017, 12:22:50 UTC · Discuss

TEAM CHALLENGE starts soon!
The first team challenge starts on March 1st, so I've temporarily increased task-in-progress limits: it's 4 tasks per CPU core + 100 tasks per GPU now. You can use the time left before the challenge to bunker more tasks.
28 Feb 2017, 7:02:40 UTC · Discuss

GPU application version
GPU application version is ~~available for beta-testing now~~ released as of February 28th. Both AMD (HD 5xxx or newer) and NVIDIA GPUs are supported. 1 GB of video RAM is required. ~~To test it, enable "Run test applications" in project preferences here: https://sech.me/boinc/Amicable/prefs.php?subset=project~~
22 Feb 2017, 13:07:00 UTC · Discuss

TEAM CHALLENGE
-------=======> Challenge standings <=======-------

SUSA has issued a Team Challenge starting 0000 UTC March 1.

Unfortunately, there was a bug in the challenge sign up SW that wouldn't allow the name Amicable Numbers to be shown in the project field. The bug was reported and has been corrected by Willy @ Bstats but he said it would take a while for project name to show up.

You can sign up your team HERE
18 Feb 2017, 6:11:30 UTC · Discuss

For all Gridcoin users: whitelist poll
A poll has been created to whitelist Amicable Numbers:
Whitelist Poll : Should Amicable Numbers Be Whitelisted?

For those who doesn't know what it is: Gridcoin website
8 Feb 2017, 17:53:24 UTC · Discuss

More than 1000 new amicable pairs found!
There are 1081 amicable pairs that have been found on the project so far!

Congratulations to everyone!
1 Feb 2017, 8:29:43 UTC · Discuss

Project is to be launched on January 30th!
Since everything is running smooth, I've decided to open the project for public tomorrow, on January 30th.
All participants will be able to choose/create teams then.
29 Jan 2017, 13:41:06 UTC · Discuss

Attention! There are very huge work units on the project now
Application is not hung if it's running the same task for many hours.
You don't need to abort it as long as you're able to finish the task within ~~2 days~~ 9 days.

My work generator is certainly not perfect, and I'll improve it before generating new work units. It was supposed to generate work units that would take no more than 2 hours on a typical 4-core Core i7 PC.

All completed huge work units will be eventually awarded with appropriate credits when they're validated.

UPDATE: I've extended deadlines for all pending tasks from 2 days to 9 days. If you have a long running task, you should check progress after 24 hours, and if it's more than 13-14%, you should be safe to finish in time.

UPDATE 2 (2017-01-25, 13:18 UTC): Work generator is now improved. New work units will be much more uniform. All work units starting with WU#4001 should have run time of no more than a few hours on 4-core processors.
24 Jan 2017, 22:54:03 UTC · Discuss

First amicable pairs found on the project
There are already 15 new amicable pairs found so far after just 12 hours of crunching!

Here is the list of new pairs: https://sech.me/ap/log/2017/2017-01-23/VOLUNTEERS%40BOINC.txt

Volunteers that found each pair are shown in the order they found this pair.

Congratulations to the people involved!
23 Jan 2017, 10:12:48 UTC · Discuss

Beta-testing
The project is currently in beta-testing phase: account creation is limited, expect bugs/instability. Once all obvious hiccups are fixed, the project will be open for public.

ETA for public launch: February 1st, 2017
19 Jan 2017, 12:15:28 UTC · Discuss

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