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Old 2016-04-30, 04:33   #1
Trejack
 

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Post Efficient testing in Pfgw

Is there a way to test two files, or prp test two different values in pfgw? (and I will get to my problem in a second) I am looking for a prime quadruplet of the form k*2^255-1, k*2^255+1, k*2^255+5, k*2^255+7. Would I be able to efficiently single-test this sequence (or combine these files, with one varible):

ABC2 $a*2^255-1
a: from 1 to 10000000000

ABC2 $a*2^255+1
a: from 1 to 10000000000

ABC2 $a*2^255+5
a: from 1 to 10000000000

ABC2 $a*2^255+7
a: from 1 to 10000000000

and get a single result like this:

k*2^255-1 is a 3-PRP! (time here)
k*2^255+1 is a 3-PRP! (time here)
k*2^255+5 is a 3-PRP! (time here)
k*2^255+7 is a 3-PRP! (time here)

And only getting results if the sequence is a prime quadruplet (or some other type). Okay for me if this is not possible, but I want to check that no one else made a dual sieve file for this before I start writing my own script for this. Thanks if there was already a dual sieve file for this.
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Old 2016-04-30, 05:13   #2
axn
 
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Jun 2003

136016 Posts
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Have you looked in the abcfileformats.txt for the "&" and "|" operators?
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Old 2016-04-30, 05:30   #3
Batalov
 
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Also, consider that if you will sieve with quad option in NewPGen (option 15), then PFGW will test the candidate quads from the candidate file more or less exactly how you want it: only once if quad member #1 is composite, two tests if chain member #1 is prime and #2 is composite and so on. It will run four tests and will report "- Complete Set -" only when all four will be prime.

Hint for TL;DR type of readers.
You want this header
[B]ABC $a*2^255-1 & $a*2^255+1 & $a*2^255+5 & $a*2^255+7[/B]
147039 255
248349 255
374244 255
436854 255
810654 255
1355484 255
1493034 255
... or equivalently
[B]4519421172:T:1:2:18563[/B]
147039 255
248349 255
374244 255
436854 255
810654 255
1355484 255
1493034 255
...
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