Programs for finding large chains of primes in arithmetic progression.

This code is developed and maintained by Bryan Little and Iain Bethune, based on several versions of the AP26 software developed since 2008.

AP26-boinc.c -- Geoffrey Reynolds, 11 September 2008.

Bryan Little 6-9-2016 BOINC enabled OpenCL Nvidia/AMD GPU AP26 app port

Modified for SSE2 support 27 September 2009 by Bryan Little NOTE this source code is for 64-bit only

Bryan Little 2 June 2016 added result hash and 10-shift search. This is a 10 shift search. Checks each K with SHIFT and SHIFT+64, SHIFT+128, ..., SHIFT+576

This file is a replacement for AP26-64.c in Jaroslaw Wroblewski's AP26 sample implementation.

See http://www.geocities.com/g_w_reynolds/AP26/AP26-boinc-src.zip for the an early version of this file.

See http://www.math.uni.wroc.pl/~jwr/AP26/AP26.zip for the sample implementation containing the rest of the source required.

See http://www.math.uni.wroc.pl/~jwr/AP26/faster32.zip for a patch to dramatically improve performance on 32-bit machines.

See http://www.math.uni.wroc.pl/~jwr/AP26/AP26v3.pdf for information about how the algorithm works and for his copyleft notice.

Makefiles are provided in the sse2 and opencl directories for Windows, Linux and Mac OS.

Compilation is controlled by the following preprocessor #defines:

• -DAP26_BOINC : Build with the BOINC library
• -DAP26_SSE2 : Build for SSE2 CPUs (64 bit)
• -DAP26_OPENCL : Build for GPUs using OpenCL

To briefly test the AP26 executable, there are reference output files in the tests/ directory. Check that the file TEST-XXXXXX.txt matches the results file SOL-AP26.txt produced by executing:

 ./AP26 XXXXXX XXXXXX 0

When testing the OpenCL app, an init_data.xml file will be needed in the directory containing GPU type and device number. See the /tests/INIT_DATA test files/ directory for examples.

search parameters are given on the command line as

 AP26 [KMIN KMAX SHIFT]

The search will begin at K=KMIN unless a file AP26-state.txt exists containing a checkpoint of the form

 KMIN KMAX SHIFT K ITER HASH LASTTRICKLE

with KMIN KMAX SHIFT matching the initial search parameters, in which case the search will resume from that checkpoint.

The search will continue up to and including K=KMAX. On completion AP26-state.txt will contain a checkpoint of the form

 KMIN KMAX SHIFT KMAX+1 ITER HASH LASTTRICKLE

Periodic checkpoints will be written to AP26-state.txt. All search results and a result hash will be appended to SOL-AP26.txt.