mersenneforum.org  

Go Back   mersenneforum.org > Math Stuff > Computer Science & Computational Number Theory > PARI/GP

Reply
 
Thread Tools
Old 2010-11-24, 20:45   #1684
CRGreathouse
 
CRGreathouse's Avatar
 
Aug 2006

3×1,993 Posts
Default

Quote:
Originally Posted by science_man_88 View Post
Digital root of the lucas lehmer residue ... really I didn't know that, Thanks. I'm just trying to limit it to a list of digital root 9 because we know the exponents must be in that group to work.
Actually, I'm not sure about my claim anymore. It would certainly be easy to compute (2+\sqrt3)^{2^{p-2}} mod 9 rather than mod 2^p-1, but that won't give you what you want since 9\not\mid2^p-1.

Of course, to me, that suggests that this is not really going to be meaningful... but that's your issue, not mine.
CRGreathouse is offline   Reply With Quote
Old 2010-11-24, 21:06   #1685
science_man_88
 
science_man_88's Avatar
 
"Forget I exist"
Jul 2009
Dumbassville

26×131 Posts
Default

Code:
3,5,7,13,17,19,23,31,33,51,61,71,89,101,107,127,139,191,271,273,305,331,347,351,367,397,405,407,427,435,457,467,489,521,525,539,543,549,559,565,577,583,589,597,601,607,611,613,617,619,641,643,661,693,717,729,787,793,809,817,819,837,871,879,891,899,983,987,991,
this is the sequence I got for lucaslehmer2()

Last fiddled with by science_man_88 on 2010-11-24 at 21:10
science_man_88 is offline   Reply With Quote
Old 2010-11-24, 22:16   #1686
3.14159
 
3.14159's Avatar
 
May 2010
Prime hunting commission.

168010 Posts
Default

Quote:
Originally Posted by science_man_88 View Post
Digital root of the lucas lehmer residue ... really I didn't know that, Thanks. I'm just trying to limit it to a list of digital root 9 because we know the exponents must be in that group to work.
Exponents? 0 mod 9? 9 does not divide any prime, so this condition is impossible to meet.

You can try 1 mod 9, 2 mod 9, 4 mod 9, 5 mod 9, 7 mod 9, and 8 mod 9.

Last fiddled with by 3.14159 on 2010-11-24 at 22:21
3.14159 is offline   Reply With Quote
Old 2010-11-25, 01:30   #1687
science_man_88
 
science_man_88's Avatar
 
"Forget I exist"
Jul 2009
Dumbassville

26×131 Posts
Default

Quote:
Originally Posted by 3.14159 View Post
Exponents? 0 mod 9? 9 does not divide any prime, so this condition is impossible to meet.

You can try 1 mod 9, 2 mod 9, 4 mod 9, 5 mod 9, 7 mod 9, and 8 mod 9.
I'm not saying anything about a prime dividing by 9 lol. If 0=9 mod 9 then you know the mersenne prime exponent residues all fit in the group of exponents with residues that are 9 mod 9, they are a subgroup.
science_man_88 is offline   Reply With Quote
Old 2010-11-25, 02:04   #1688
3.14159
 
3.14159's Avatar
 
May 2010
Prime hunting commission.

24·3·5·7 Posts
Default

Quote:
Originally Posted by science_man_88 View Post
I'm not saying anything about a prime dividing by 9 lol. If 0=9 mod 9 then you know the mersenne prime exponent residues all fit in the group of exponents with residues that are 9 mod 9, they are a subgroup.
Okay.. what about it?

Last fiddled with by 3.14159 on 2010-11-25 at 02:11
3.14159 is offline   Reply With Quote
Old 2010-11-25, 03:20   #1689
3.14159
 
3.14159's Avatar
 
May 2010
Prime hunting commission.

24·3·5·7 Posts
Default

And;

Adding Fermat's factoring algorithm was rather easy;

Code:
fmtfcs(a, x, m) = {
for(n=a,x,
if(issquare(n^2+m), print(n))
);
}
Okay; A few edits to that..

Revision:
Code:
fmtfcs(a,x,m)=for(n=a,x,if(issquare(n^2+m),print(sqrtint(n^2+m)+n, " * ", sqrtint(n^2+m)-n)));

Last fiddled with by 3.14159 on 2010-11-25 at 03:27
3.14159 is offline   Reply With Quote
Old 2010-11-25, 03:40   #1690
CRGreathouse
 
CRGreathouse's Avatar
 
Aug 2006

3·1,993 Posts
Default

Bad Pi! Functions should return, not print. What if you wanted to use that data from another program?
CRGreathouse is offline   Reply With Quote
Old 2010-11-25, 12:55   #1691
3.14159
 
3.14159's Avatar
 
May 2010
Prime hunting commission.

168010 Posts
Default

Quote:
Originally Posted by CRGreathouse View Post
Bad Pi! Functions should return, not print. What if you wanted to use that data from another program?
Okay, fine. I've changed it to "return". Nope, that's unable to return the factors. Back to printing it goes.

I'm busy collecting relations for a c106. I'm only about ... 31% done. 159k relations are needed. So, I estimate that this will take two or three days. (I've only collected 49105 relations, so far, given eight hours.)

Last fiddled with by 3.14159 on 2010-11-25 at 13:17
3.14159 is offline   Reply With Quote
Old 2010-11-25, 15:41   #1692
3.14159
 
3.14159's Avatar
 
May 2010
Prime hunting commission.

24·3·5·7 Posts
Default

If adding Fermat's was easy.. How would one go about in adding an amateur QS?

(Yes, yes, I know that PARI already uses MPQS.)

My knowledge of it so far is;

1. Set bound.
2. Set factor base.
3. b-smooth congruence hunting.
4. Try to set ≥2 congruences into a congruence of squares.
5. gcd.
6. Factors.

Last fiddled with by 3.14159 on 2010-11-25 at 15:47
3.14159 is offline   Reply With Quote
Old 2010-11-25, 15:53   #1693
3.14159
 
3.14159's Avatar
 
May 2010
Prime hunting commission.

24×3×5×7 Posts
Default

I did a comparison, and it seems that trial division by far outspeeds the Fermat script.

I think I didn't have the most efficient script there is.. But I'll try improving on it.

I'm now 2/3 done with the collection of relations for the c106 I'm trying to split (Hopefully it does not crash.)|

Update: 72% done.

Last fiddled with by 3.14159 on 2010-11-25 at 16:53
3.14159 is offline   Reply With Quote
Old 2010-11-25, 18:31   #1694
3.14159
 
3.14159's Avatar
 
May 2010
Prime hunting commission.

110100100002 Posts
Default

Record split; Part 3!

Code:
starting SIQS on c106: 4475950135356613778937951617143741209311215873146646798431494279597781200242083780419779316018232365322301

==== sieving in progress ( 4 threads):  159064 relations needed ====
====            Press ctrl-c to abort and save state            ====
159188 rels found: 35794 full + 123394 from 2418802 partial, ( 48.30 rels/sec)

SIQS elapsed time = 51034.7770 seconds.


***factors found***

PRP53 = 59032375916416525973964206982565204661985227334884669
PRP53 = 75821954747240330698482729033441429926359516470800129
3.14159 is offline   Reply With Quote
Reply

Thread Tools


Similar Threads
Thread Thread Starter Forum Replies Last Post
Why do I sometimes see all the <> formatting commands when I quote or edit? cheesehead Forum Feedback 3 2013-05-25 12:56
Passing commands to PARI on Windows James Heinrich Software 2 2012-05-13 19:19
Ubiquity commands Mini-Geek Aliquot Sequences 1 2009-09-22 19:33
64-bit Pari? CRGreathouse Software 2 2009-03-13 04:22
Are these commands correct? jasong Linux 2 2007-10-18 23:40

All times are UTC. The time now is 23:06.


Fri Aug 6 23:06:56 UTC 2021 up 14 days, 17:35, 1 user, load averages: 4.21, 3.93, 3.92

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2021, 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.