20151030, 22:02  #1 
"Mark"
Apr 2003
Between here and the
14042_{8} Posts 
Mathworld, and ReverseSmarandache Primes
I've been in contact with Eric Weinstein (who manages the Mathworld website). He is interested in some of the searches being done by mersenneforum and PrimeGrid. If you are interested in doing something "different", check out these links:
http://mathworld.wolfram.com/Consecu...Sequences.html http://mathworld.wolfram.com/ConstantPrimes.html http://mathworld.wolfram.com/IntegerSequencePrimes.html I've invited Eric to join (or rejoin) mersenneforum. I think that with the brains on this forum we should be able to develop some projects to extends the searches. One in particular is for SmarandacheWellin primes (see separate thread). I've already modified pfgw to support that form natively and would be willing to modify pfgw for other searches. I am also willing to help write sieving code for some of those searches. If you are interested in any of those searches, start a new thread to drum up some interest. 
20151030, 22:14  #2 
"Forget I exist"
Jul 2009
Dumbassville
2^{6}·131 Posts 
well I look up a lot sometimes and I know that there's quite a few threads related to this like the smarandache primes thread. and a puzzle about the reversing concatenation version of the sequence, pi primes semi relate to the primes in pi thread though that's slightly different.

20151030, 23:10  #3 
"Serge"
Mar 2008
Phi(4,2^7658614+1)/2
10010000101110_{2} Posts 
Good luck with PrimeGrid!
When I posted there about the ongoing Smarandache prime search, my post was removed as spam and I've been given a lecture by email. Not automatically generated, mind you, no  hand written and, in particular, comparing my posting to "selling shoes". I cannot believe that someone would be so deluded as to consider PrimeGrid volunteer resources as somehow their subordinates and "protect" that workforce from "leaking" to other potential projects, and zealously censoring their forum from such dangerous postings. They own that workforce, it seems. But that's ok. I've seen the Communist Party and I've seen censorship  nothing new here; I can recognize the same symptoms in people, and I know towards what bright future they will march their masses on. They own them. NIH. "Not Invented Here". A sadly familiar attitude. 
20151031, 02:23  #4  
"Serge"
Mar 2008
Phi(4,2^7658614+1)/2
242E_{16} Posts 
Interestingly, after checking PNACP (Crandal, Pomerance, 2005, 2nd ed., p.78
Quote:


20151102, 15:53  #5 
Oct 2015
19 Posts 
Yes, the comment in question applied to the 1st edition but the reference got updated to the 2nd edition, where it no longer applies. Fixed on http://mathworld.wolfram.com/Smarand...llinPrime.html

20151102, 16:04  #6 
Oct 2015
19_{10} Posts 
p#1 and OEIS A057704
It seems https://oeis.org/A057704
2, 3, 5, 6, 13, 24, 66, 68, 167, 287, 310, 352, 564, 590, 620, 849, 1552, 1849 misses recently found large p#1 primes; cf. e.g. http://primes.utm.edu/top20/page.php?id=5 and http://prpnet.primegrid.com:12008/user_primes.html. Does anyone know the complete list of additional primes to bring it up to date? I.e., are there any other primes between 1587#  1 and 843301#  1? 
20151103, 03:07  #7 
"Serge"
Mar 2008
Phi(4,2^7658614+1)/2
2×11×421 Posts 
Hi Eric,
Welcome back to the forum! I had a question about Smr(n) primes: you have found the second PRP in 2010 (n=37765), but how far did you search? Are you still searching? 
20151103, 04:10  #8  
Sep 2002
Database er0rr
3,533 Posts 
Quote:
Last fiddled with by paulunderwood on 20151103 at 04:13 

20151103, 12:13  #9 
Oct 2015
23_{8} Posts 
Thanks.
Yes, still searching. As of today the search has reached 47889 47888 ... 3 2 1 without finding any more PRPs. 
20151103, 14:18  #10 
Oct 2015
19 Posts 
Indeed. Another question for Paul or anyone else (I am having trouble rejoining primeform on Yahoo groups to ask there.) I see PrimeGrid has been busily finding new Thabit ibn Kurrah primes 3*2^n  1. I found some references to that search in various places:
https://groups.yahoo.com/neo/groups/...messages/11558 http://primes.utm.edu/bios/page.php?id=950 http://www.primegrid.com http://boinc.berkeley.edu However, I did not manage to find a page listing the current status/search limits. Any know if there is one? Also, may I infer from the above that Paul's 321 search http://www.mersenneforum.org/321sear...%20search.html is no longer active? Thanks. 
20151103, 14:52  #11 
"Carlos Pinho"
Oct 2011
Milton Keynes, UK
2^{4}·3·101 Posts 

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