mersenneforum.org  

Go Back   mersenneforum.org > Prime Search Projects > Twin Prime Search

Reply
 
Thread Tools
Old 2006-05-06, 21:05   #12
gribozavr
 
gribozavr's Avatar
 
Mar 2005
Internet; Ukraine, Kiev

11·37 Posts
Default

biwema,

I'm now at p=20T. I'll start another sieving of [5e9; 25e9] and when it reaches 20T, I will merge them. I will start just now, so there is not much work to catch up.
gribozavr is offline   Reply With Quote
Old 2006-05-12, 19:10   #13
gribozavr
 
gribozavr's Avatar
 
Mar 2005
Internet; Ukraine, Kiev

11·37 Posts
Default

I have merged [150e6; 5e9] and [5e9; 25e9] this morning. Now the whole range [150e6; 25e9] is at p=21.4T, 10,947,000 k's left, rate is about 1 k/sec.
gribozavr is offline   Reply With Quote
Old 2006-05-13, 02:43   #14
MooooMoo
Apprentice Crank
 
MooooMoo's Avatar
 
Mar 2006

2×227 Posts
Thumbs up

Quote:
Originally Posted by gribozavr
I have merged [150e6; 5e9] and [5e9; 25e9] this morning. Now the whole range [150e6; 25e9] is at p=21.4T, 10,947,000 k's left, rate is about 1 k/sec.
Excellent progress!
MooooMoo is offline   Reply With Quote
Old 2006-05-16, 16:18   #15
gribozavr
 
gribozavr's Avatar
 
Mar 2005
Internet; Ukraine, Kiev

11·37 Posts
Default

I have released [150e6; 200e6] for LLR at p=30.6T. Now the range [200e6; 25e9] is at p=30.6T, 10,667,000 k's left, rate is ~1.4-1.6 k/sec.

MooooMoo's edit: The ranges are now in the "pre sieved range reservation thread".

Last fiddled with by MooooMoo on 2006-05-17 at 07:34
gribozavr is offline   Reply With Quote
Old 2006-05-30, 18:31   #16
gribozavr
 
gribozavr's Avatar
 
Mar 2005
Internet; Ukraine, Kiev

1100101112 Posts
Default

Now the range [250e6; 25e9] is at p=51.7T, 10,334,553 k's left, rate is ~2.5-2.7 k/sec.
gribozavr is offline   Reply With Quote
Old 2006-06-03, 13:08   #17
gribozavr
 
gribozavr's Avatar
 
Mar 2005
Internet; Ukraine, Kiev

6278 Posts
Default

Now the range [250e6; 25e9] is at p=61.0T, 10,226,786 k's left, rate is ~2.5-2.7 k/sec.
gribozavr is offline   Reply With Quote
Old 2006-06-11, 08:55   #18
R. Gerbicz
 
R. Gerbicz's Avatar
 
"Robert Gerbicz"
Oct 2005
Hungary

2·3·233 Posts
Default

Quote:
Originally Posted by MooooMoo
Probability of finding a twin in a range:
my calculations of n=195000 give...
range
k=5 G chance of finding a twin: 31%
k=10 G chance of finding a twin: 52%
k=20 G chance of finding a twin: 77%
k=25 G chance of finding a twin: 84%
k=30 G chance of finding a twin: 89%
k=40 G chance of finding a twin: 95%
k=50 G chance of finding a twin: 97.5%
I can confirm that your calculation is correct. Here it is a small ( PARI ) program to compute the probabilities from 5G to 50G step by 5G:

Code:
T=4.0;forprime(p=3,10^5,T*=(p-2)/p/(1-1/p)^2);p=T*(195000*log(2))^-2;\
forstep(i=5,50,5,print("k=",i," G ","chance of finding a twin: ",1-(1-p)^(i*10^9/2)))
k=5 G chance of finding a twin: 0.3032663771235724704662848430
k=10 G chance of finding a twin: 0.5145622587534880610868001205
k=15 G chance of finding a twin: 0.6617792038603679416316561856
k=20 G chance of finding a twin: 0.7643501993734845214281243748
k=25 G chance of finding a twin: 0.8358148606793800287773442252
k=30 G chance of finding a twin: 0.8856066930586734521235834760
k=35 G chance of finding a twin: 0.9202983368219543694155290908
k=40 G chance of finding a twin: 0.9444691714646835051627448017
k=45 G chance of finding a twin: 0.9613098046532592367695271155
k=50 G chance of finding a twin: 0.9730432400262686098144673574
About the first 5 digits of the probabilities is correct.
R. Gerbicz is offline   Reply With Quote
Old 2006-06-11, 10:31   #19
biwema
 
biwema's Avatar
 
Mar 2004

38110 Posts
Default

Nice.

My Approach was slightly different: I was a bit afraid on how much the thiw is dependant on each other. Therefor I sieved a range of 10G to K=1T, and did the probability calculation with the number of remaining candidates to minimize the dependency. Ofcourse, this number has also a statistical distribution.
biwema is offline   Reply With Quote
Old 2006-06-13, 21:46   #20
gribozavr
 
gribozavr's Avatar
 
Mar 2005
Internet; Ukraine, Kiev

1100101112 Posts
Default

The range [300e6; 25e9] is at p=83.0T, 10,005,865 k's left, rate is ~5.0-8.0 sec/k.

Please excuse me, in posts #15, #16 and #17 I made a mistake: I wrote "k/sec", while it is "sec/k".
gribozavr is offline   Reply With Quote
Old 2006-06-14, 23:15   #21
biwema
 
biwema's Avatar
 
Mar 2004

3·127 Posts
Default

hi gribozavr,

Could it be, that you are quite unlucky?


Quote:
Originally Posted by gribozavr
I have released [150e6; 200e6] for LLR at p=30.6T. Now the range [200e6; 25e9] is at p=30.6T, 10,667,000 k's left, rate is ~1.4-1.6 k/sec.
Quote:
Originally Posted by gribozavr
The range [300e6; 25e9] is at p=83.0T, 10,005,865 k's left
My Calculation gives:

10667000 * (24.7G / 24.8G) * (Log2(30.6T) / Log2(83T))^2 = 9972751 Candidates, so there are 28500 Factors too few.

Candidates * New Range * Newfactoring Depth ratio^twin

Is there a flaw in my calculations?

Edit:
More detailed calculations with excel give:
3.06E+13 24.8 10667000
5.17E+13 24.75 10334553 10294806 39747
6.10E+13 24.75 10226768 10227121 -353
8.30E+13 24.7 10005867 10010909 -5042

from 30.6T to 51.7T 39747 too few factors;
from 51.7T to 61T approx. correct
from 61T to 83T 5000 too many

Last fiddled with by biwema on 2006-06-14 at 23:32
biwema is offline   Reply With Quote
Old 2006-06-24, 20:05   #22
gribozavr
 
gribozavr's Avatar
 
Mar 2005
Internet; Ukraine, Kiev

11·37 Posts
Default

The range [400e6; 25e9] is at p=101.1T, 9,849,791 k's left, rate is ~5.0-10.0 sec/k.

Sieving has passed 100T

biwema, I'm intrested in this math, but I don't understand the "Newfactoring Depth ratio" part. Can you explain it to me, please? (I undersatnd that log2(x) is the number of bits in x)
gribozavr is offline   Reply With Quote
Reply

Thread Tools


Similar Threads
Thread Thread Starter Forum Replies Last Post
S9 and general sieving discussion Lennart Conjectures 'R Us 31 2014-09-14 15:14
Sieving discussion thread philmoore Five or Bust - The Dual Sierpinski Problem 66 2010-02-10 14:34
Combined sieving discussion ltd Prime Sierpinski Project 76 2008-07-25 11:44
Sieving Discussion ltd Prime Sierpinski Project 26 2005-11-01 07:45
Sieving Discussion R.D. Silverman Factoring 7 2005-09-30 12:57

All times are UTC. The time now is 08:23.

Tue Sep 29 08:23:43 UTC 2020 up 19 days, 5:34, 0 users, load averages: 1.80, 1.65, 1.66

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2020, Jelsoft Enterprises Ltd.

This forum has received and complied with 0 (zero) government requests for information.

Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or any later version published by the Free Software Foundation.
A copy of the license is included in the FAQ.