20211107, 06:16  #34 
Jan 2007
Germany
2^{2}×107 Posts 
updated

20211113, 23:16  #35  
"Serge"
Mar 2008
Phi(4,2^7658614+1)/2
3×7×461 Posts 
Quote:
533098369554*2357#+3399421517+30*n, n=0..5 (1012 digits) 

20211113, 23:23  #36  
Sep 2002
Database er0rr
29×137 Posts 
Quote:


20211113, 23:58  #37  
"Serge"
Mar 2008
Phi(4,2^7658614+1)/2
22721_{8} Posts 
Quote:
I am thinking about merging sieve with PFGW some time later (for larger CPAPs), or else the sieved files are wasting rather large disk space (even though I use the ABCD format). TL;DR: Larger CPAPs actually require quite a different approach as well. For CPAP4 through CPAP6, this form with carefully chosen A=3399421517, k*p# ± (A+30*n) is a nearly guaranteed hit sequence (in appropriate limits, i.e. p<9929), except for one composite to test (with 3399421549). But with higher forms, k*p# ± (C+210*n), it is easy to obtain 7 or 8 primes but a fat subset of intermediates will also have a chance of being prime. Interesting "minimaxtype" challenge. 

20211114, 00:06  #38  
Sep 2002
Database er0rr
F85_{16} Posts 
Quote:
I found precomputing the primorial shaved off ~8% of PRP'ing when I ran AP8. You need GWNUM skilz for it. Last fiddled with by paulunderwood on 20211114 at 00:08 

20211114, 00:37  #39  
"Serge"
Mar 2008
Phi(4,2^7658614+1)/2
10010111010001_{2} Posts 
Quote:


20211114, 04:23  #40 
Jan 2007
Germany
2^{2}·107 Posts 
is updated
Last fiddled with by Cybertronic on 20211114 at 04:30 
20211114, 06:11  #41  
"99(4^34019)99 palind"
Nov 2016
(P^81993)SZ base 36
23×139 Posts 
Quote:


20211115, 02:20  #42 
"Serge"
Mar 2008
Phi(4,2^7658614+1)/2
3·7·461 Posts 
CPAP7
And, to warm up,  a small update to CPAP7 (leading to possible CPAP8 and/or CPAP9):
2022541154997*619#+x253+210*n, n=0..6 (271 digits) Don't ask about intermediates. They are all sieved out. But you can check: replace 210* by 2* ... 
20211115, 04:19  #43 
Jan 2007
Germany
2^{2}·107 Posts 
is updated
Is there a chance to find a CPAP7 without a big constant ,like this:
k*1261#/2154317507668859 + B1+d,d=0,210,...1260 [>500 digits] ??? Last fiddled with by Cybertronic on 20211115 at 04:31 
20211115, 05:44  #44 
"Serge"
Mar 2008
Phi(4,2^7658614+1)/2
3×7×461 Posts 

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