mersenneforum.org  

Go Back   mersenneforum.org > Extra Stuff > Miscellaneous Math

Reply
 
Thread Tools
Old 2010-09-07, 17:12   #364
3.14159
 
3.14159's Avatar
 
May 2010
Prime hunting commission.

24×3×5×7 Posts
Default

I'm guessing it will continually overflow until it reaches the necessary trial factoring limit.

Quote:
Originally Posted by Charles
So how long do you expect it to take, compared to your earlier efforts?
About 400-700 times as long as the previous effort. The previous effort took about 10 minutes. This is going to take 2-3 days.

I'm abandoning this one. It is too long and too costly. I have inadequate comp power to outbest the number you submitted anytime soon.

I'm going back to looking for larger primes.

Last fiddled with by 3.14159 on 2010-09-07 at 17:21
3.14159 is offline   Reply With Quote
Old 2010-09-07, 17:26   #365
wblipp
 
wblipp's Avatar
 
"William"
May 2003
New Haven

44768 Posts
Default

Quote:
Originally Posted by 3.14159 View Post
Code:
P.S: Can someone prove the primality of the number 29201806527798202690471270497026289647897695441591089473790387382190437432352472117744280333628938004491474620381040060030880069981 
using trial factoring alone?
It depends on the definition of "trial factoring alone." I can easily prove that it is prime where the only factoring done is trial factoring - does that count as "trial factoring alone?"

(Generate an N-1 proof. Trial factoring will easily completely factor N-1, and no other factoring is necessary to complete the proof).

Last fiddled with by wblipp on 2010-09-07 at 17:28 Reason: added code tage
wblipp is offline   Reply With Quote
Old 2010-09-07, 18:09   #366
CRGreathouse
 
CRGreathouse's Avatar
 
Aug 2006

3×1,993 Posts
Default

Quote:
Originally Posted by 3.14159 View Post
About 400-700 times as long as the previous effort. The previous effort took about 10 minutes. This is going to take 2-3 days.

I'm abandoning this one. It is too long and too costly. I have inadequate comp power to outbest the number you submitted anytime soon.
I'm hoping to submit a number so large that you won't even bother trying to top it. I estimate that my current number would take you 3-5 months.
CRGreathouse is offline   Reply With Quote
Old 2010-09-07, 18:18   #367
science_man_88
 
science_man_88's Avatar
 
"Forget I exist"
Jul 2009
Dumbassville

20C016 Posts
Default

Quote:
Originally Posted by CRGreathouse View Post
Pi, I started work on a second number as soon as I finished the first. Your number shouldn't take too long, so you'll probably get a record before I smash it.



Good luck. If you find an answer, post it -- and tell me if mine is OK.
best I found so far :


General Rules
1. Has no factors below 2^30<- replace with step 2 of trial factor for trial factored primes.
2. Passes a pseudoprimality test (Recommendation: 1-3 bases)
3. Is not a "small" prime. (Please ensure it is ≥ 1000 digits.)

Trial factor
Step 1. Pick a number.
Step 2. Trial division up to its square root.
Step 3. If prime, report here.

Categories
1. Generalized Proths, where b is any integer.
i.Proths, where b is 2.
ii.Proths, where b is a factorial number.
iii.Proths, where b is a primorial number.
iv.Proths, where b is a prime number.
2. Primorial, k * p(n) + 1
3. Factorial, k * n! + 1
4. Generalized Cullen/Woodall, k * b^k + 1
i.Factorial Cullen/Woodall, where b, optionally k, is a factorial number.
ii.Primorial Cullen/Woodall, where b, optionally k, is a primorial number.
iii.Prime-based Cullen/Woodall, where b is a prime number
5. k-b-b, numbers of the form k * b^b + 1
i.Factorial k-b-b, where b, optionally k, is a factorial number.
ii.Primorial k-b-b, where b, optionally k, is a primorial number.
iii.Prime-based k-b-b, where b is a prime number.
6. Number, square, and fourth, where n^1 + 1, n^2 + 1, and n^4 + 1 are all primes.
7. Special Cofactor, where the prime cofactor is of one of the forms used in this list.
8 .General Cofactor, where the prime cofactor is not of a special form.
9. General arithmetic progressions, k * b^n + c, where c is a prime > 10^2, where the prime is at least 2000 digits in length, and where the exponent n > 1.
10. Obsolete-tech-proven primes, using the original PrimeForm or Proth.exe, or any other prime to prove primality of any type of prime listed here. Note: The prime must be at least 7500 digits in length.
11 .N-1 analogues of items in 1.
a. k>1 for the analogue of 1i
12. N-1 analogues of items 2 and 3.
13. N-1 analoges of items 8-11.
14. N-1 analogues of items 12-15.
15. Obsolete-tech-proven primes, for -1 analogues only.
16. Twins.

arithmetic progressions
Every odd prime is indeed part of an arithmetic progression, either 2n + 1, or 6n ± 1. It's in fact impossible for an odd prime not to be in an arithmetic progression.

no fermats or mersennes

no special form primes -> Yes, they are all special-form primes.

Last fiddled with by science_man_88 on 2010-09-07 at 18:21
science_man_88 is offline   Reply With Quote
Old 2010-09-07, 18:29   #368
science_man_88
 
science_man_88's Avatar
 
"Forget I exist"
Jul 2009
Dumbassville

100000110000002 Posts
Default

okay technically if I did my research proper all until 5iii can go under 1
science_man_88 is offline   Reply With Quote
Old 2010-09-07, 18:38   #369
3.14159
 
3.14159's Avatar
 
May 2010
Prime hunting commission.

24·3·5·7 Posts
Default

Quote:
Originally Posted by science_man_88
okay technically if I did my research proper all until 5iii can go under 1
Cullen-Woodalls are not Proths. What a load of

Last fiddled with by 3.14159 on 2010-09-07 at 18:39
3.14159 is offline   Reply With Quote
Old 2010-09-07, 18:38   #370
science_man_88
 
science_man_88's Avatar
 
"Forget I exist"
Jul 2009
Dumbassville

26·131 Posts
Default

though Wikipedia says k*2^n+1 not k*b^n+1
science_man_88 is offline   Reply With Quote
Old 2010-09-07, 18:40   #371
3.14159
 
3.14159's Avatar
 
May 2010
Prime hunting commission.

168010 Posts
Default

Quote:
Originally Posted by science_man_88
though Wikipedia says k*2^n+1 not k*b^n+1
Sorry, buddy, you debunked yourself.

Quote:
Originally Posted by Chris Caldwell
Though actually not a true class of primes, the primes of the form k * 2n+1 with 2n > k are often called the Proth primes.

Last fiddled with by 3.14159 on 2010-09-07 at 18:42
3.14159 is offline   Reply With Quote
Old 2010-09-07, 18:40   #372
science_man_88
 
science_man_88's Avatar
 
"Forget I exist"
Jul 2009
Dumbassville

20C016 Posts
Default

Quote:
Originally Posted by 3.14159 View Post
Cullen-Woodalls are not Proths. What a load of
not what Wikipedia is saying :

The Cullen numbers are the special case of Proth numbers with k = n.
The Fermat numbers are a special case of the Proth numbers with k = 1.

Woodalls no Cullens unless i misinterpret what is said are.
science_man_88 is offline   Reply With Quote
Old 2010-09-07, 18:42   #373
science_man_88
 
science_man_88's Avatar
 
"Forget I exist"
Jul 2009
Dumbassville

26×131 Posts
Default

Quote:
Proths, where b is 2.
Wikipedia is saying Proth = k*2^n+1 so b=2 is general specification according to that.

Last fiddled with by science_man_88 on 2010-09-07 at 18:44
science_man_88 is offline   Reply With Quote
Old 2010-09-07, 18:44   #374
3.14159
 
3.14159's Avatar
 
May 2010
Prime hunting commission.

110100100002 Posts
Default

Quote:
Originally Posted by science_man_88
not what Wikipedia is saying :

The Cullen numbers are the special case of Proth numbers with k = n.
The Fermat numbers are a special case of the Proth numbers with k = 1.

Woodalls no Cullens unless i misinterpret what is said are.
Lie by omission, you did not include that b = 2.

Where b != 2, it is Generalized Cullen-Woodalls, which are on the list, which are not Proth numbers, which is where b = 2.

The categories of my list remain at 26, 20 of which I will search for.

Last fiddled with by 3.14159 on 2010-09-07 at 18:47
3.14159 is offline   Reply With Quote
Reply

Thread Tools


Similar Threads
Thread Thread Starter Forum Replies Last Post
Prime posting thread, part 2. (With a catch.) 3.14159 Miscellaneous Math 55 2010-11-19 23:55
Tiny range request .... 555.1M petrw1 LMH > 100M 1 2010-07-13 15:35
Other primes thread nuggetprime No Prime Left Behind 32 2009-10-21 21:48
Error: tiny factoring failed 10metreh Msieve 26 2009-03-08 23:28
Tiny error on nfsnet pages. antiroach NFSNET Discussion 1 2003-07-08 00:27

All times are UTC. The time now is 22:51.


Fri Aug 6 22:51:08 UTC 2021 up 14 days, 17:20, 1 user, load averages: 3.71, 4.06, 3.90

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.