In this co-ordinated search, Yves Gallot's Proth software can be used to generate primoproths for p# = 11# to 23#. A note here, standard convention for this and some other software asks for values of the formulae k.b^n+/-1. k is an odd number, and b is the base, in this case 2. As all primorials are even numbers it is necessary to adapt the formulae accordingly. For k=23#, use the value 23#/2 = 111546435, as 23# is too large a number for this software to handle.
Values of p# up to 23# can be sieved using Paul Jobling's NewPGen . You should use version 2.60 which enables larger Primoproths to be sieved. Note: With this software you should use primorial mode and choose one of the two primoproth options.
There are several primality provers which can be used, with or without sieves.
Primeform by Chris Nash and others. However Primeform is no longer supported by its authors and is in many respects deficient. Please note that Primeform only provides probable primes for p#2^n-1. In Primeform, choose "expression" under the mode option, and type in either k#.2^n-1 or +1 in the expression box.
So rather than that, pfgw is what this group is using. It is less user friendly than Primeform but way faster and can prove primality for p#.2^n-1. If you are using a sieve prepared with NewPGen is ready it is necessary to edit the first line of the output file to include the instruction ABC $a#*2^$b+1 When running pfgw your command line at the dos prompt will then read something like pfgw sievefilename -loutputfilename
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