20050420, 16:48  #89  
"Sander"
Oct 2002
52.345322,5.52471
29·41 Posts 
Quote:
But i choose this one because i can't use that pc for anything else (except maybe ecm) and it's only available to me for a few days. PRPing takes only 15 minutes on my P4. The pc will be gone tomorrow morning and i didn't want to let it run idle. For the last year or two, i spent most of my cpu time factoring for a few projects (including Paul's). Unfortunately, Cunningham numbers are a bit to hard for my limited resources. I might be able to do a < c140 with GNFS, but my P4 has only 256MB RAM. I have a laptop with 2GB, but that one is used for work, and part of that memory is often needed. Besides, i'm not sure GGNFS is upto the job yet. Sieving on multiple pc's requires to much book keeping for the time i've currentely got. I'm open for any number you want to have factored, as long as it can be done in a reasonable amount of time. 

20050420, 16:53  #90 
"Sander"
Oct 2002
52.345322,5.52471
2245_{8} Posts 
N=157
Below the results for N=157 and K<2*10^13
All are prp, not tested for primality Code:
541364899635*2^157+1 541364899635*2^1571 541364899635*2^(157+1)+1 541364899635*2^(157+1)1 2^157+541364899635 2^157541364899635 2^(157+1)+541364899635 2^(157+1)541364899635 5375998941495*2^157+1 5375998941495*2^1571 5375998941495*2^(157+1)+1 5375998941495*2^(157+1)1 2^157+5375998941495 2^1575375998941495 2^(157+1)+5375998941495 2^(157+1)5375998941495 7137839620995*2^157+1 7137839620995*2^1571 7137839620995*2^(157+1)+1 7137839620995*2^(157+1)1 2^157+7137839620995 2^1577137839620995 2^(157+1)+7137839620995 2^(157+1)7137839620995 16986089468655*2^157+1 16986089468655*2^1571 16986089468655*2^(157+1)+1 16986089468655*2^(157+1)1 2^157+16986089468655 2^15716986089468655 2^(157+1)+16986089468655 2^(157+1)16986089468655 
20050420, 17:17  #91  
421_{8} Posts 
Silverman
Quote:
This project has been around for awhile, and now has a new spin on the fundamental property that started it. 

20050420, 22:32  #92 
Jun 2003
Suva, Fiji
2^{3}·3·5·17 Posts 
Angels
We would still be computing the number of angels on the head of a pin unless we had adapted and explored.
The facts are: This is original thinking, adaptation and exploration in virgin territory It is simple, but not so simple, there are pitfalls for the unwary There is interesting mathematics if anyone wants to look at it Axn1's program is a masterpiece This is true 1+1=3, as I like to define human cooperation This is the shitzit right now Mr Silverman, have pity on us poor humans, nattering together and taking up your valuable bandwidth. Consider yourself flamed, or at least singed, as I am a pacific sort. Regards Robert Smith (aged 53 1/4) 
20050421, 03:15  #93 
Aug 2004
Melbourne, Australia
2^{3}×19 Posts 
What's in a name?
Silverman? Hmmm... sounds familiar. Are you related to Joseph H. Silverman who published (among others) the paper "Wieferich's Criterion and the abcConjecture" in the Journal of Number Theory?

20050421, 05:14  #94 
Aug 2004
Melbourne, Australia
10011000_{2} Posts 
Predicting the next octoproth.
I've been looking at the "weights" of certain bases again. Working as I defined it previously, W(157) = 62. Is the heaviest W(n) for n <= 200.
The next three heaviest are W(175) = 60 W(187) = 56 W(112) = 54 So the bases n = 112, 175, 187 should be good for finding octos. 
20050421, 13:04  #95 
Aug 2004
Melbourne, Australia
2^{3}×19 Posts 
Update
Newies:
4358737887315 87 (a monster!) 2232065722095 88 2148136610235 88 for n=8996 there are no known octoproths. Searched n=89 to k=780321515295. 
20050422, 04:26  #96  
13·467 Posts 
bitwin
Quote:
With RMA 1.75 in 2 minutes I was able to find no octoproth's for n=5000, with k<200000000. TTn 

20050422, 06:25  #97  
"Sander"
Oct 2002
52.345322,5.52471
1189_{10} Posts 
Quote:
Quote:
Code:
1297905 5000 111183135 5000 116381265 5000 176976555 5000 Last fiddled with by smh on 20050422 at 06:26 

20050422, 06:49  #98  
2·1,453 Posts 
Quote:
Although not all those look like the same candidates I came up with. hmmm... Ill double check. 

20050422, 15:35  #99 
10001000101111_{2} Posts 
double check
Ah, newpgen has caused some errors due to the large file size.
Or machine/Os cannot handle correctly. I am surprised that you are getting so much speed without errors. If this is true, then congradulations! I will tricheck thouroughly, with a belts and braces technique. TTn 
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