20121216, 06:01  #353 
Jun 2009
2×5×67 Posts 
Hi Norman,
thanks! It is the nature of records that they will be broken some day. Let's see who will take primo to the next level. 
20121217, 00:19  #354 
"Phil"
Sep 2002
Tracktown, U.S.A.
1117_{10} Posts 
Congratulations, Peter and Marcel! Thanks also to Norman, whose previous work helped Marcel update Primo to the current multicore version. Only 18 more probable primes to certify to prove the dual Sierpinski conjecture as a theorem!

20130116, 17:12  #355 
Jun 2009
2×5×67 Posts 
I tried the next candidate, 2^73360+10711 but it wouldn't get past test1. It seems we reached the end of primo's useful range.

20130116, 22:09  #356 
Just call me Henry
"David"
Sep 2007
Cambridge (GMT/BST)
165A_{16} Posts 
Might be worth waiting until http://mersenneforum.org/showthread.php?t=17554 is a viable option.
The method needs to be checked and a program needs to be made public. If ecpp ran in O(x) then this runs in O(x^(3/4)). In other words a lot faster once overhead is insignificant. 
20130117, 17:26  #357 
"Phil"
Sep 2002
Tracktown, U.S.A.
1,117 Posts 
Thanks for trying this. I had hoped that maybe the next two, 2^73360+10711 and 2^73845+14717, might yield to primo. I wonder if your log file would be of use to Marcel Martin in case he might be interested in extending the capabilities of the program.

20130117, 22:10  #358 
Jun 2009
2×5×67 Posts 
So did I hope but Marcel Martin did not sound very interested in making major changes to primo. I am afraid this is the end of that path.

20130117, 22:19  #359 
Just call me Henry
"David"
Sep 2007
Cambridge (GMT/BST)
2×2,861 Posts 
It might be worth trying 2^73845+14717. You were unlucky with the smaller one that there was nowhere to backtrack to since it was the first iteration. Maybe that will be more lucky.

20130117, 22:48  #360 
"Serge"
Mar 2008
Phi(4,2^7658614+1)/2
2×3^{3}×13^{2} Posts 
...and Peter, you probably already cranked the factoring limits to the top (2^32), right?
_______________ P.S. I started an 8thread test on 2^73845+14717 (no intent to finish!) and the .cr file says that it moved on to the 2nd test... but look at that gain! ;) [1] Type=4 Gain=3 Index=1.10120 D=335755 H/G=96/8:12 Last fiddled with by Batalov on 20130118 at 09:17 
20130118, 17:08  #361  
Jun 2009
670_{10} Posts 
Quote:
Quote:
Gain=3 woohoo ;) I'll have to think about this. I'd love to do some real biggies but the risk of losing lots of time is considerable... Last fiddled with by PuzzlePeter on 20130118 at 17:09 

20130118, 18:55  #362 
"Serge"
Mar 2008
Phi(4,2^7658614+1)/2
9126_{10} Posts 
Actually, as I now look at the primo GUI window (I didn't have access to the terminal before, so I simply read the .CR file)  the gain is not just 3 bits. The progress is show as "Test 2  Bits 73784/73846", so I don't have a good grasp of the semantic of the "Gain" line. But of course the stalling scenario like you described would be impossible to predict just yet.
If it gets to say Test 10, I can forward you the package? Another way in the old "Luhnization" routine would be to deliberately start from the very beginning many times in parallel, avoiding the paths already taken by other "threads". 
20130118, 19:58  #363 
Jun 2009
1236_{8} Posts 
I kept a close eye on my primo runs and so far the "Gain=" value always equalled the bit difference from one test to the next. I have no idea what to think of your numbers.
OK I see you're trying every trick in the book to get me enticed. Right. You win. Take it to test 10 and I'll take over ;) EDIT: What does the .cr file say now? There might have been a backtrack. First path gave a gain of 3 bits which means the next step will give up and backtrack rather early (backtracking is dependent from various factors, one of them being the gain that is sacrificed by going back one step), then a better Step1 with a larger gain was found. Last fiddled with by PuzzlePeter on 20130118 at 20:03 
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