mersenneforum.org  

Go Back   mersenneforum.org > Search Forums

Showing results 1 to 25 of 1000
Search took 0.28 seconds.
Search: Posts Made By: paulunderwood
Forum: Homework Help 2021-10-28, 15:11
Replies: 7
Views: 167
Posted By paulunderwood
This sub-forum is for help not complete...

This sub-forum is for help not complete solutions!

Anyway, I'd like to see an LL test. I.e. isPrime(p,sqrt(p))&&passesLL((1<<p)-1). :boxer:
Forum: Science & Technology 2021-10-28, 14:42
Replies: 4
Views: 153
Posted By paulunderwood
I have just had my 3rd shot of Pfizer -- the...

I have just had my 3rd shot of Pfizer -- the booster -- and not feeling any adverse symptoms yet...:smile:
Forum: Homework Help 2021-10-28, 08:05
Replies: 7
Views: 167
Posted By paulunderwood
:lol: Hah, good point! If the numbers are less...

:lol: Hah, good point! If the numbers are less than 1,000,000 then the problem is greatly reduced. You need to do trial division for p<=19, (maybe trail division of Mp by 2*k*p+1), and an LL test....
Forum: Homework Help 2021-10-28, 07:34
Replies: 7
Views: 167
Posted By paulunderwood
Firstly you need to address multiple-precision...

Firstly you need to address multiple-precision through the use of limbs or an array of integers. Does your program deal with overflow beyond 64 bits? Are you allowed to use a library such as GMP?
...
Forum: Hardware 2021-10-26, 20:53
Replies: 8
Views: 285
Posted By paulunderwood
LL is a method that relies on the Lucas-Lehmer...

LL is a method that relies on the Lucas-Lehmer theorem.

LLR is a program written by Jean Penne base on George Woltman's library. LLR also refers to the Lucas-Lehmer-Riesel theorem, although the...
Forum: Miscellaneous Math 2021-10-26, 05:03
Replies: 32
Views: 3,380
Posted By paulunderwood
version for bash

The attached program returns exit(0) iff the input is 2-Euler PRP and Lucas PRP. (It also uses gcd((r-1)*(2*r-1),n-1)<=2.)

// gcc -o prp_v2 prp_v2.c -lgmp
// bash use case:-
/*
for i in...
Forum: Information & Answers 2021-10-25, 21:37
Replies: 8
Views: 213
Posted By paulunderwood
A couple of options might be: Add this to...

A couple of options might be:

Add this to your remote crontab @reboot /path/to/mprime/mprime &. You might like to investigate the screen command.

Or prepend nohup to your mprime command.
Forum: Miscellaneous Math 2021-10-24, 18:32
Replies: 26
Views: 939
Posted By paulunderwood
Thanks for the link. Isn't this what...

Thanks for the link.

Isn't this what Prime95/mprime and gpuowl use already?
Forum: Miscellaneous Math 2021-10-24, 17:09
Replies: 26
Views: 939
Posted By paulunderwood
Do you have a link to the said publication?

Do you have a link to the said publication?
Forum: Miscellaneous Math 2021-10-24, 15:38
Replies: 32
Views: 3,380
Posted By paulunderwood
2 selfidge version

We can fuse the Euler and Lucas test thusly:


{
tst(n,r)=local(fr=lift(Mod(4,n)^r));
gcd((r-1)*(2*r-1),n-1)<=2&&
kronecker(fr-8,n)==-1&&
Mod(Mod(2*x,n),x^2-(fr/2-2)*x+1)^((n+1)/2)==2;
}
Forum: Miscellaneous Math 2021-10-24, 08:25
Replies: 32
Views: 3,380
Posted By paulunderwood
A slight speed up

Rather than taking gcd(4^r-4,n)==1 and gcd(4^r-2,n)==1 the substitute gcd((r-1)*(2*r-1),n-1)<=2 is quicker, resulting in the test:


{
tst(n,r)=local(k=kronecker(2,n);fr=lift(Mod(4,n)^r));...
Forum: PrimeNet 2021-10-22, 18:06
Replies: 13
Views: 508
Posted By paulunderwood
There is no need to restart your number (after...

There is no need to restart your number (after throttling). You can be very confident with any number of Gerbicz errors. :smile:
Forum: Riesel Prime Search 2021-10-22, 18:03
Replies: 290
Views: 50,286
Posted By paulunderwood
PRP tests for these are quite quick, compared to...

PRP tests for these are quite quick, compared to proofs. However they need generic modular reduction for Fermat PRP tests, whereas small-k Riesel and Proth prime run 4x (?) faster using a special...
Forum: PrimeNet 2021-10-22, 17:36
Replies: 13
Views: 508
Posted By paulunderwood
On warmer days this might be a problem. Is it a...

On warmer days this might be a problem. Is it a stock Intel cooler? Would you consider getting an all-in-one water cooler?

I have run Intel chips at these temperatures, but if heat builds in the...
Forum: Miscellaneous Math 2021-10-22, 11:21
Replies: 26
Views: 939
Posted By paulunderwood
I barely understand the necessity but would have...

I barely understand the necessity but would have to refer to the LL wiki page (https://en.wikipedia.org/wiki/Lucas%E2%80%93Lehmer_primality_test#Proof_of_correctness) for sufficiency.
Forum: Miscellaneous Math 2021-10-22, 01:11
Replies: 26
Views: 939
Posted By paulunderwood
The LL test is performed with different hardware...

The LL test is performed with different hardware and different software for 100% confidence,
Forum: PrimeNet 2021-10-21, 12:50
Replies: 13
Views: 508
Posted By paulunderwood
Find out why you are getting Gerbicz errors. In...

Find out why you are getting Gerbicz errors. In the first place check your thermals with some temperature monitoring software. Other than this voltage and timings are crucial. What is the...
Forum: Miscellaneous Math 2021-10-20, 02:59
Replies: 32
Views: 3,380
Posted By paulunderwood
GMP code for test #3

I have coded up test #3 from the above paper.


// gcc -o prp prp.c -lgmp
// usages:-
// ./prp
// ./prp <integer>
// echo "print(<expression>)" | gp -q | ./prp
Forum: Miscellaneous Math 2021-10-19, 11:50
Replies: 26
Views: 939
Posted By paulunderwood
We do a 3-PRP test because it uses a very...

We do a 3-PRP test because it uses a very reliable Gerbicz Error Correcting algorithm. If a Mersenne number is found to be 3-PRP we then proceed to an LL test. The chances of a 3-PRP not passing an...
Forum: Riesel Prime Search 2021-10-18, 22:55
Replies: 290
Views: 50,286
Posted By paulunderwood
Two birds with one stone

Congrats tp Ryan and Serge for the record Near-rep Digit / Palindrome prime 10^1888529 - 10^944264 - 1 (https://primes.utm.edu/primes/page.php?id=132851)
Forum: Riesel Prime Search 2021-10-18, 20:18
Replies: 438
Views: 84,099
Posted By paulunderwood
k=23

We would like to reserve k=23 from n=5,000,000 under "Underwood et al" :smile:
Forum: Miscellaneous Math 2021-10-18, 14:11
Replies: 26
Views: 939
Posted By paulunderwood
Err, Nick, n^2^p would be n^2 mod Mp. Usually we...

Err, Nick, n^2^p would be n^2 mod Mp. Usually we use "a" not "n" and n=2^p-1.
Forum: Software 2021-10-18, 13:59
Replies: 508
Views: 100,220
Posted By paulunderwood
Thanks head -n1 Downloads/helper.ini | wc ...

Thanks

head -n1 Downloads/helper.ini | wc
1 1 21

Whereas 520461*2^55931+1 has 16+2 characters if Windows. Did you copy this number from the net?


cat -A...
Forum: Software 2021-10-18, 13:44
Replies: 508
Views: 100,220
Posted By paulunderwood
Please attach your helper file for inspection....

Please attach your helper file for inspection. :smile:

Use the forum's paperclip.
Forum: Software 2021-10-18, 11:08
Replies: 508
Views: 100,220
Posted By paulunderwood
If you have copy and pasted a number into the...

If you have copy and pasted a number into the helper file, especially from the web, it might have non-printable characters in it. Please attach the file "xyz".
Showing results 1 to 25 of 1000

 
All times are UTC. The time now is 17:38.


Thu Oct 28 17:38:06 UTC 2021 up 97 days, 12:07, 0 users, load averages: 1.80, 1.67, 1.53

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.