Posts by Sergei Chernykh

1) Message boards : Number crunching : 23 Pair Finder Method (Message 2265)
Posted 5 days ago by Sergei Chernykh
Post:
Good work! This is a similar method to what I used for finding all 21-digit pairs with the largest prime factor of the smaller number being > 1014. I just took all pairs of numbers from certain ranges and tried to match them using the similar equations to what you used for P2 and P5 (but in general form). You probably already noticed that 22-, 23-, 24- and bigger-digit known amicable numbers (up to around 36-digit) have a lot of amicable numbers with large prime factors in them. This is a by-product of that search.

P.S. Keep searching using your method - this is also a good independent check of the 1021 search, because your method is also exhaustive.
2) Message boards : News : Unplanned maintenance (Message 2262)
Posted 6 days ago by Sergei Chernykh
Post:
Time since a WU was marked for a transition (usually for validation).
3) Message boards : News : Part 3 of the 10^21 search has started (Message 2258)
Posted 11 days ago by Sergei Chernykh
Post:
I'm pretty certain there's also methods listed online of how to mass find N,1 pairs.

Yes, there are :) https://sech.me/ap/articles.html
4) Message boards : Number crunching : Validation / Credit (Message 2180)
Posted 25 Jan 2026 by Sergei Chernykh
Post:
Completed tasks pile up when they arrive faster than the server can process them. This is what's happening now - it's 5+ hours backlog at the moment.
5) Message boards : Bug tracker : Anyone else running out of work? (Message 2176)
Posted 25 Jan 2026 by Sergei Chernykh
Post:
The server is struggling with the current load. I've increased the target "Tasks ready to send" from 5000 to 30000, so even if it drops below 30k, hopefully it will still stay above 0.
6) Message boards : Number crunching : Support for Intel Panther Lake Xe3 iGPUs (Arc B390) (Message 2162)
Posted 17 Jan 2026 by Sergei Chernykh
Post:
Unfortunately the project is at end-of-life stage. It will be finished in early March, so there is no point to do more development work for it now. But that hardware you'll be getting looks really interesting though, I'm sure it will be very competitive on any BOINC project!
7) Message boards : News : Part 3 of the 10^21 search has started (Message 2144)
Posted 2 Nov 2025 by Sergei Chernykh
Post:
There will be part 4 and it will take approximately 6 months. There are no other plans after that, so the project will most likely finish.
8) Message boards : News : Part 3 of the 10^21 search has started (Message 2134)
Posted 14 Oct 2025 by Sergei Chernykh
Post:
The WUs for part 4 should take 5-6 months to process at the current speed. So maybe you will be able to get to 1 billion :)
9) Message boards : News : Part 3 of the 10^21 search has started (Message 2132)
Posted 13 Oct 2025 by Sergei Chernykh
Post:
Top credit badge is given for 1 billion credits, so probably not... Part 4 shouldn't find any new amicable pairs, that's the whole point of it - it will double check the exhaustive searches I did before in that range.
10) Message boards : News : Part 3 of the 10^21 search has started (Message 2130)
Posted 10 Oct 2025 by Sergei Chernykh
Post:
I estimated that 1021 would take 40 years, and it took 6 years only: https://sech.me/boinc/Amicable/forum_thread.php?id=77&postid=614#614

But it's mostly thanks to the other exhaustive searches I did for largest prime factors > 1014. If not for them, the current search would have to continue up until 5*1019, and that's at least another 6 years.
11) Message boards : News : Part 3 of the 10^21 search has started (Message 2127)
Posted 5 Oct 2025 by Sergei Chernykh
Post:
There will be one more part for 1021, several months worth of tasks - it will check largest prime factors > 1014 to confirm that all amicable numbers are already found in that range.

As for 1022 - I'm not sure it's feasible. The current search took 6 years, so 1022 should take more than 60 years (the scaling is a bit worse than linear)...
12) Message boards : News : Unplanned maintenance (Message 2125)
Posted 4 Oct 2025 by Sergei Chernykh
Post:
Maintenance finished, everything should be back to normal now.
13) Message boards : News : Unplanned maintenance (Message 2124)
Posted 4 Oct 2025 by Sergei Chernykh
Post:
Also unsent tasks are piling up.

Yes, this is a part of server tuning that I've been doing.
14) Message boards : News : Unplanned maintenance (Message 2123)
Posted 4 Oct 2025 by Sergei Chernykh
Post:
I will turn on file uploader and task scheduler soon, as soon as all pending WUs are validated. It should happen in ~30 minutes.
15) Message boards : News : Unplanned maintenance (Message 2120)
Posted 4 Oct 2025 by Sergei Chernykh
Post:
Until "Workunits waiting for validation" clears. There has been an increase in computing power in the last few days, so I'm tweaking the server in the meantime. It should clear in 2-3 hours.
16) Message boards : News : Unplanned maintenance (Message 2118)
Posted 4 Oct 2025 by Sergei Chernykh
Post:
Workunit and task distribution is temporarily off until the backlog of WUs clears.

Edit: Maintenance finished, everything should be back to normal now.
17) Message boards : News : Part 3 of the 10^21 search has started (Message 2114)
Posted 22 Sep 2025 by Sergei Chernykh
Post:
There is no larger WUs, at least in terms of used GPU memory,
18) Message boards : News : Part 3 of the 10^21 search has started (Message 2111)
Posted 20 Sep 2025 by Sergei Chernykh
Post:
Part 3 completes when the largest prime factor in M reaches 1014. Currently it's at ~3*1013. As for P_max > 1014, all amicable pairs in that range should already be known thanks to a few exhaustive searches I did on my own, using a different approach. But to double check it, I will run the regular search in the range 1014...1015 - this will be part 4 of the search.
19) Message boards : Number crunching : Auto-ban faulty hosts (Message 2099)
Posted 23 Aug 2025 by Sergei Chernykh
Post:
No hosts are banned at the moment.
20) Message boards : Number crunching : How do I increase number of pending downloadable GPU tasks for BOINC? (Message 2098)
Posted 23 Aug 2025 by Sergei Chernykh
Post:
The server can handle the current load. And the number of requests depends more on a single task size, which I already doubled not so long time ago.
21) Message boards : Bug tracker : Wrong operating system (Message 2089)
Posted 11 Aug 2025 by Sergei Chernykh
Post:
Changes in 8.2.4

Win:

Use BOINC WSL distro if present


WSL = Windows Subsystem for Linux, and yes it is Ubuntu under the hood.
22) Message boards : Bug tracker : Amicable pairs counter defect? (Message 2080)
Posted 17 Jun 2025 by Sergei Chernykh
Post:
We're searching through numbers of the form "X*P" where P is a very large prime number. There are not many amicable pairs of this form. In fact, I estimate that there are only 300-400 amicable pairs left to discover in the current search.
23) Message boards : Number crunching : Android support? (Message 2072)
Posted 16 May 2025 by Sergei Chernykh
Post:
Amicable use 32-bit integers

64-bit integers for the most part, because we're dealing with 21-, 22-digit numbers already.
24) Message boards : Bug tracker : Issue with arm64-apple-darwin (Message 2056)
Posted 9 Apr 2025 by Sergei Chernykh
Post:
Your other Macs run x86_64-apple-darwin version, so I guess they use Rosetta. This is not an optimal way, but it's the best for Apple Silicon for now on this project. I need to finally add support for arm64-apple-darwin platform when I have more free time.
25) Message boards : News : WU size and credits are doubled now (Message 2049)
Posted 3 Apr 2025 by Sergei Chernykh
Post:
No, task sizes are the same now. Maybe your GPU or the room it's in got more warm?
26) Message boards : Number crunching : FYI. Some credits didn't post correctly to the consolidators (Message 2039)
Posted 5 Mar 2025 by Sergei Chernykh
Post:
Credits are given out when two users finish the same task, so it depends on who you got paired with for each task.
27) Message boards : News : WU size and credits are doubled now (Message 2032)
Posted 25 Feb 2025 by Sergei Chernykh
Post:
All these tasks have the same amount of work, so the same amount of points. I don't know why your GPU processed them slower - maybe something else was using the GPU?
28) Message boards : Number crunching : Intel Arc B580 (Message 2028)
Posted 20 Feb 2025 by Sergei Chernykh
Post:
I've updated the regex, it's 
Intel\(R\) (Arc|Graphics)
now. Your GPU should start getting tasks now.
29) Message boards : Number crunching : Intel Arc B580 (Message 2026)
Posted 19 Feb 2025 by Sergei Chernykh
Post:
Not "they", it's me. I set 
<host_summary_regex>Arc</host_summary_regex>
in the project's settings. If you can suggest a better regex that covers all Intel Arc GPUs, I'll be thankful.
30) Message boards : Number crunching : Intel Arc B580 (Message 2024)
Posted 19 Feb 2025 by Sergei Chernykh
Post:
The project limits Intel GPUs to only ones that have "Arc" in their host summary text (i.e. Intel Arc GPUs). This is done to avoid integrated Intel GPUs as they're almost useless. If you can fix your host's description to include "Arc" in GPU name, it will start receiving tasks.
31) Message boards : Number crunching : How do I increase number of pending downloadable GPU tasks for BOINC? (Message 2013)
Posted 4 Feb 2025 by Sergei Chernykh
Post:
This is the server-side limitation. I put max 4 tasks per GPU in the config long time ago. There are different BOINC competitions that run on Amicable Numbers from time to time, and this is to prevent people from fetching a lot of tasks before the competition starts to submit them and get credits as soon as it starts.
32) Message boards : Number crunching : Nvidia RTX 50-seris - estimated Amicable Numbers performance? (Message 2005)
Posted 27 Jan 2025 by Sergei Chernykh
Post:
Then I looked at 4060 Ti which has an average of 440.5 sec but mine consistently completes < 287 or almost a 4070 Ti. I wish they had four columns on the GPU page: linux, win 11, win 10 and "other".

It also depends on how many parallel tasks per GPU you run. You should check "tasks per 24 hours" metric instead.
33) Message boards : Bug tracker : Computing - CPU models - Apple Silicon? (Message 1999)
Posted 19 Jan 2025 by Sergei Chernykh
Post:
Apple Silicon CPU/GPU applications are not available officially, but it's possible to build it manually and run it under the BOINC's "anonymous platform". Some people do.

P.S. You can download the unofficial Apple Silicon GPU application from https://github.com/SChernykh-team/actions/actions/runs/11844297083 (scroll down for the build artifacts) - I tried to build it to check if it's possible, and it built fine and ran fine.
34) Message boards : Random stuff : website dark mode and donation (Message 1982)
Posted 29 Dec 2024 by Sergei Chernykh
Post:
There is a "Dark Reader" extension for Chrome that can fix it for all websites that you visit.

This project is self-funded, and runs on one server so I don't need to spend a lot of money on it and there is no need for donations.
35) Message boards : Bug tracker : OpenCL_Intel_GPU not giving work, application not found (Message 1981)
Posted 29 Dec 2024 by Sergei Chernykh
Post:
From the project config:
	<plan_class>
		<name>opencl_intel_gpu</name>
		<opencl/>
		<gpu_type>intel</gpu_type>
		<host_summary_regex>Arc</host_summary_regex>
		<min_gpu_ram_mb>2600</min_gpu_ram_mb>
		<gpu_ram_used_mb>2600</gpu_ram_used_mb>
		<cpu_frac>0.0001</cpu_frac>
	</plan_class>

So it should be an Intel Arc GPU - if there is no "Arc" in the host description, it will not work.
36) Message boards : Number crunching : Apple M-series CPU/GPU Applications (Message 1970)
Posted 15 Nov 2024 by Sergei Chernykh
Post:
Technically it's possible to build the binaries for the arm64-apple-macos-11 compiler target. But first I need to figure out how to add arm64 macOS platform to the project because it didn't even exist when this project started.
37) Message boards : News : WU size and credits are doubled now (Message 1967)
Posted 9 Nov 2024 by Sergei Chernykh
Post:
I've increased the deadline for new work units to 1 week. It is enough for all modern CPUs, if you run BOINC on more than 1 CPU core.
38) Message boards : Random stuff : MacOS support? (Message 1964)
Posted 5 Nov 2024 by Sergei Chernykh
Post:
Yes, see the list of supported platforms: https://sech.me/boinc/Amicable/apps.php
39) Message boards : Bug tracker : No GPU work for AMD/ATI GPU since 09:00 UTC (Message 1961)
Posted 29 Oct 2024 by Sergei Chernykh
Post:
You can check Computing -> Server status page: https://sech.me/boinc/Amicable/server_status.php

It says 3235 tasks ready to send right now.

Edit: you already have 4 in-progress tasks, and the project doesn't let you to have more (per GPU).
40) Message boards : News : WU size and credits are doubled now (Message 1955)
Posted 28 Oct 2024 by Sergei Chernykh
Post:
No, GPU and CPU RAM requirements stay the same.
41) Message boards : News : WU size and credits are doubled now (Message 1953)
Posted 28 Oct 2024 by Sergei Chernykh
Post:
First of all, thanks to everyone participating in the project!

I've noticed today that solved work units come in so fast that the server can't keep up. I had to double the size of each work unit (together with the credit for it) to reduce the load on the server.

Keep crunching! Thanks again!
42) Message boards : Bug tracker : Workunits that are stuck but both computers finished the task 2024/10/26 (Message 1951)
Posted 28 Oct 2024 by Sergei Chernykh
Post:
Update: someone added a lot of computing power to the project, so WUs are piling up right now - but all scripts are working. I'm keeping an eye on the server in the meantime.
43) Message boards : Number crunching : GPU version: kernel size tuning and less UI lags (Message 1950)
Posted 28 Oct 2024 by Sergei Chernykh
Post:
If you're not getting full GPU utilization on RTX 4090, it's better to run several WUs per GPU in parallel than to increase the kernel size above 23.
44) Message boards : Bug tracker : Workunits that are stuck but both computers finished the task 2024/10/26 (Message 1947)
Posted 26 Oct 2024 by Sergei Chernykh
Post:
I've restarted all services to be sure that they're not stuck.
45) Message boards : Bug tracker : Workunits that are stuck but both computers finished the task 2024/10/26 (Message 1946)
Posted 26 Oct 2024 by Sergei Chernykh
Post:
No, it's not stuck. Just every time I'm running some HDD-intensive tasks on the server, validation starts lagging. I stopped these tasks now.
46) Message boards : News : Maintenance on 2024-11-07 (7th of November) (Message 1943)
Posted 24 Oct 2024 by Sergei Chernykh
Post:
Project server will be unavailable on 2024-11-07 (7th of November), from 03:30 AM UTC to 05:30 AM UTC due to the maintenance in a Hetzner datacenter where the server is hosted.
47) Message boards : Random stuff : Russia and Ukraine (Message 1942)
Posted 22 Oct 2024 by Sergei Chernykh
Post:
No politics here. If it puts your mind at ease, I'm the only scientist/developer on Amicable Numbers, and I live in Sweden.
48) Message boards : Bug tracker : Workunits that are stuck but both computers finished the task 2024/10/07 (Message 1937)
Posted 8 Oct 2024 by Sergei Chernykh
Post:
I've added a script to unstuck such WUs. They shouldn't be stuck for more than an hour now.
49) Message boards : Bug tracker : Workunits that are stuck but both computers finished the task 2024/10/07 (Message 1936)
Posted 8 Oct 2024 by Sergei Chernykh
Post:
I've fixed it. Normally it shouldn't happen so there is no need for such script. I was restarting services recently, maybe this is why some WUs got stuck.
50) Message boards : Bug tracker : No GPU work for AMD/ATI GPU since 09:00 UTC (Message 1933)
Posted 6 Oct 2024 by Sergei Chernykh
Post:
I've restarted all services. Let me know if it solved this issue.


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