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gcwsieve

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gcwsieve/gcwsievecl
Workload type Siever
First release
Latest version 1.5.1
2023-03-24

Description

gcwsieve (and gcwsievecl) are used to create sieve files for a (General) Woodall prime or (General) Cullen prime sequence.

The CPU version of this program was originally written by Geoffrey Reynolds. It is currently developed by Mark Rodenkirch, who merged it into the packaged distribution of mtsieve and added GPU support.

Commands overview

Help with gcwsieve -h.

Installation

Create a folder containing the sieve program.

Creating a new sieve

Example:

gcwsieve.exe -s- -b1024 -n2 -N5000 -P1000000000

Parameters:

  • -s-: using Woodall (Cullen: -s+)
  • -b1024: using base 1024
  • -n2: lowest n-value
  • -N5000: highest n-value
  • -P1000000000: highest prime to search for

After running the file "gcw_b1024.pfgw" in ABC fileformat will be created.

Continuing an existing sieve file

To continue the search call this (from example above):

gcwsieve.exe -P2000000000 -igcw_b1024.pfgw

Parameters:

  • -P2000000000: the new sieve-depth is given
  • -igcw_b1024.pfgw: the standard output from first run is used as input file

See also

Sieving program