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CRGreathouse 2010-11-24 20:45

[QUOTE=science_man_88;238535]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.[/QUOTE]

Actually, I'm not sure about my claim anymore. It would certainly be easy to compute [TEX](2+\sqrt3)^{2^{p-2}}[/TEX] mod 9 rather than mod [TEX]2^p-1,[/TEX] but that won't give you what you want since [TEX]9\not\mid2^p-1.[/TEX]

Of course, to me, that suggests that this is not really going to be meaningful... but that's your issue, not mine.

science_man_88 2010-11-24 21:06

[CODE][COLOR="Red"]3,5,7,13,17,19,[/COLOR]23,[COLOR="red"]31,[/COLOR]33,51,[COLOR="red"]61,[/COLOR]71,[COLOR="red"]89,[/COLOR]101,[COLOR="red"]107,127,[/COLOR]139,191,271,273,305,331,347,351,367,397,405,407,427,435,457,467,489,[COLOR="red"]521,[/COLOR]525,539,543,549,559,565,577,583,589,597,601,[COLOR="red"]607,[/COLOR]611,613,617,619,641,643,661,693,717,729,787,793,809,817,819,837,871,879,891,899,983,987,991,[/CODE]

this is the sequence I got for lucaslehmer2()

3.14159 2010-11-24 22:16

[QUOTE=science_man_88;238535]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.[/QUOTE]

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.

science_man_88 2010-11-25 01:30

[QUOTE=3.14159;238561]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.[/QUOTE]

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.

3.14159 2010-11-25 02:04

[QUOTE=science_man_88;238577]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.[/QUOTE]

Okay.. what about it?

3.14159 2010-11-25 03:20

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))
);
}[/code]

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)));[/code]

CRGreathouse 2010-11-25 03:40

Bad Pi! :wink: Functions should return, not print. What if you wanted to use that data from another program?

3.14159 2010-11-25 12:55

[QUOTE=CRGreathouse;238588]Bad Pi! :wink: Functions should return, not print. What if you wanted to use that data from another program?[/QUOTE]

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.)

3.14159 2010-11-25 15:41

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.

3.14159 2010-11-25 15:53

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.

3.14159 2010-11-25 18:31

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
[/code]


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