I came across this [URL="http://mersenneforum.org/showthread.php?t=9479"]thread[/URL] for the example which is in post 3. Esecially after looking at that thread i don't know how I missed it. Now I think about it more closely (88996/4)*2^2+1=88996*2^0+1 is prime and removes 88996/4 and 88996/2 but not 88996. Sorry for missing the obvious MOB stuff. My excuss is that today was the last day of term at school. :party:
edit: thanks for the interesting history
I presume PSP missed the even ks for the second conjecture because of SOB not having any remaining. I only realized that PSP was searching the second conjecture last month. :smile:

[quote=henryzz;221613]
I presume PSP missed the even ks for the second conjecture because of SOB not having any remaining. I only realized that PSP was searching the second conjecture last month. :smile:[/quote]

Huh? You better reread my post.

1. PSP is only searching prime k's so would not test even k's.

2. PSP is not searching the 2nd conjecture. That project has not changed other than the fact that they are partnering with PrimeGrid for some of their n-ranges. As always, they are searching the 1st prime conjecture.

3. It is PrimeGrid's "extended Sierpinsi project" that is searching the 2nd conjecture. They missed searching even k's.

4. I'm fairly certain that PrimeGrid did not test even k's because the original Riesel and Sierp conjectures only stated "odd k's". It likely had nothing to do with the fact that there were no even k's remaining for k<78557.

I had forgotten about that thread that you provided the link to. Now i know that the prime that you stated was not coincidence. One note about that: GFNs are not considered in the conjecture just like k's with trivial factors are not. For that reason even though k=65536 does not have a prime, it does not need one nor is it considered the conjecture. It has been agreed by many that a large # of GFNs are unlikely to ever have primes.

The starting bases script came in especially handy with the even k search. Since it knows to only search even k's where k+1 is prime, it eliminated a lot of work up front on k's where an associated odd k would have (or eventually have) the same prime with a slightly different n-value.

Karsten, Max, and/or Vmod,

My apologies for dragging my feet on this: So that I don't have to search around for them, could whomever sees this first provide me with links to the various "cool" webpages that you guys have worked on that contain:

1. A condensed summary of the bases done by Karsten.
2. Bases with 1/2/3 k's remaining done by Karsten.
3. All of the excellent stats on the various bases done by Vmod's scripts.

Although I may not have given the impression previously, I believe these are all excellent pages that will make the project more interesting to future searchers.

What I will do is add them as links in the 1st post here after the reservations links so that people see them quickly when first visiting the project.

Thanks! :smile:


Gary

[QUOTE=gd_barnes;236921]1. A condensed summary of the bases done by Karsten.
2. Bases with 1/2/3 k's remaining done by Karsten.
3. All of the excellent stats on the various bases done by Vmod's scripts.
[/QUOTE]

No.1 and 3 are shown [url=http://www.noprimeleftbehind.net/crus/]here[/url] (lower two links) and updated every 15mins.

No.2 is included in No.1 with different colors, a separate page is not shown.

Thanks Karsten. Links are now provided in the 1st posting here under "General short summary pages". Both are now very nice automated summarized lists for the project and should encourage future searchers to break some CRUS records or fill in some holes. :smile:

[QUOTE=gd_barnes;120738]For starting a new entire base, I suggest PFGW.

If you still want to bite off part of a new base like this, let me know and I'll send you a PM that will have detailed instructions on downloading PFGW and setting up the parameters properly.

I will post what software to use including PFGW for all of the various searches and detailed instructions about their set up and how to use them in the next couple of hours but I won't go into how to start a new base like this, which would require way too many different instructions for the different situations on the many bases.

I know this doesn't answer your question completely but now that you know the above, if you can let me know how you want to proceed, I can taylor the answers more to what you want to do.

Gary[/QUOTE]

Could you give me instructions on how to start a new base? I am familiar with srxsieve, tpsieve, LLR, NewPGen and I have played around with PFGW a bit. But I don't know how to get started. Is there an elegant way of keeping track of the eliminated k's in the beginning when primes are found in milliseconds? I don't like the idea of using an Excel sheet at this stage.

Just for fun I tried b=150, n=2 and it gave me thousands of primes. I feel quite flooded and don't know what to do with them. :blush::rolleyes:

Thanks
Peter

Thanks a lot,
Peter

[QUOTE=Puzzle-Peter;247479]Could you give me instructions on how to start a new base? I am familiar with srxsieve, tpsieve, LLR, NewPGen and I have played around with PFGW a bit. But I don't know how to get started. Is there an elegant way of keeping track of the eliminated k's in the beginning when primes are found in milliseconds? I don't like the idea of using an Excel sheet at this stage.

Just for fun I tried b=150, n=2 and it gave me thousands of primes. I feel quite flooded and don't know what to do with them. :blush::rolleyes:[/QUOTE]

Start with [URL="http://www.mersenneforum.org/showthread.php?t=9742"]this[/URL] thread. Look for bases that haven't been started [URL="http://www.mersenneforum.org/showthread.php?t=12983"]here[/URL] and [URL="http://www.mersenneforum.org/showthread.php?t=12984"]here[/URL].

Thanks!

I realize there is a lot to digest in the software thread. For starting new bases, here is a snippet that will narrow it down for you:

[quote]
(2) When starting a new base, run PFGW version 3.4.0 or later using the [URL="http://www.noprimeleftbehind.net/crus/new-bases-4.3.txt"]new-bases-4.3[/URL] script as an input file. Then use the following command to run it:
"(script name) -f100 -l". -f100 will cause it do to a 'normal amount' of initial factoring. See above for -l. Regarding the script file, there are very simple instructions in the script. There are only 5 lines that need to be changed for each base.
[/quote]

One thing that I'll mention: We don't ever recommend using NewPGen here. It is highly inefficient at sieving multiples k's over large n-ranges, which is usually what we need. sr2sieve is almost always best; tpsieve has not been developed for bases other than 2. For a base with 1 k-value remaining, sr1sieve is best.

Thank you! One last question: when using the script for starting a new base, will kmin equal 1 or 2? 2 is default, is 1 excluded for some reason?

IMPORTANT:
ALL Sierp/Riesel bases < 1030 have been searched to some extent.
Look here
[URL]http://www.noprimeleftbehind.net/crus[/URL]