mersenneforum.org  

Go Back   mersenneforum.org > Factoring Projects > FactorDB

Reply
 
Thread Tools
Old 2011-11-24, 05:50   #23
Batalov
 
Batalov's Avatar
 
"Serge"
Mar 2008
Phi(4,2^7658614+1)/2

2×7×677 Posts
Default

How 'bout this? 2837!^2+2837!+1 (a.k.a. Phi(3,2837!) )

This one will be a bit harder (will need some more factoring and a CHG on it) - Phi(5,2415!)

These extend A051856 and A200906
Batalov is offline   Reply With Quote
Old 2011-11-24, 15:56   #24
wblipp
 
wblipp's Avatar
 
"William"
May 2003
New Haven

93E16 Posts
Default

Quote:
Originally Posted by Batalov View Post
How 'bout this? 2837!^2+2837!+1 (a.k.a. Phi(3,2837!)
How'd ya do dat? Factordb says it has an N-1 proof, but N-1 shows no known factors.
wblipp is offline   Reply With Quote
Old 2011-11-24, 20:59   #25
Batalov
 
Batalov's Avatar
 
"Serge"
Mar 2008
Phi(4,2^7658614+1)/2

2·7·677 Posts
Default

Well, in the same way as Phi(3,6001!) :-]

(just submitted it to a worker for a PRP test -- and the FactorDB apparently finds all 6001! factors one by one because it takes an inordinate amount of time, but when it does, it realizes that N-1 with the next prime is in order)
Batalov is offline   Reply With Quote
Old 2011-11-25, 16:23   #26
RichD
 
RichD's Avatar
 
Sep 2008
Kansas

337610 Posts
Default

Spotted (10^1296*13-7)/123 in the PRP list. Applying the algebraic factors to N-1 was not quite enough to prove it prime, but a few clicks on the scan button provided the one more needed factor.
RichD is offline   Reply With Quote
Old 2011-11-26, 02:20   #27
RichD
 
RichD's Avatar
 
Sep 2008
Kansas

24×211 Posts
Default

Another cute one (2^5367*7+1)/57 was proven by N-1 method.

<Taking a break for the night.>

Edit: (10^1621*77-41)/729 by N-1.

Last fiddled with by RichD on 2011-11-26 at 02:40 Reason: Add one more.
RichD is offline   Reply With Quote
Old 2011-11-26, 06:53   #28
Batalov
 
Batalov's Avatar
 
"Serge"
Mar 2008
Phi(4,2^7658614+1)/2

250616 Posts
Default

Quote:
Originally Posted by RichD View Post
Another cute one (2^5367*7+1)/57 was proven by N-1 method.

<Taking a break for the night.>

Edit: (10^1621*77-41)/729 by N-1.
Well, in the same way as Phi(3,7606!) :-]


<Taking a break for the night.>
Batalov is offline   Reply With Quote
Old 2011-11-26, 08:09   #29
Batalov
 
Batalov's Avatar
 
"Serge"
Mar 2008
Phi(4,2^7658614+1)/2

947810 Posts
Default

Phi(3,7076!) :-] in fact...
Batalov is offline   Reply With Quote
Old 2011-11-26, 16:10   #30
wblipp
 
wblipp's Avatar
 
"William"
May 2003
New Haven

2×7×132 Posts
Default

(10^1365*88-97)/9 by N+1 by adding the algebraic factors of 10^1365-1
wblipp is offline   Reply With Quote
Old 2011-11-28, 21:23   #31
RichD
 
RichD's Avatar
 
Sep 2008
Kansas

1101001100002 Posts
Default

(5^2498+1)/26 is proven prime by applying the algebraic factors of 5^2496-1 to N-1.

(191*2^6105-1)/381 is proven prime by applying the algebraic factors of 2^6104-1 to N-1.
RichD is offline   Reply With Quote
Old 2011-11-28, 23:40   #32
RichD
 
RichD's Avatar
 
Sep 2008
Kansas

64608 Posts
Default

(10^1900+3)/7 is proven prime by applying the algebraic factors of 10^1899+1 to N+1.
RichD is offline   Reply With Quote
Old 2011-11-29, 00:13   #33
cmd
 
cmd's Avatar
 
"(^r'°:.:)^n;e'e"
Nov 2008
;t:.:;^

33·37 Posts
Cool

Quote:
Originally Posted by Batalov View Post
Phi(3,7076!) :-] in fact...
then ...
Attached Thumbnails
Click image for larger version

Name:	ff96682.jpg
Views:	267
Size:	178.1 KB
ID:	7321  
cmd is offline   Reply With Quote
Reply

Thread Tools


Similar Threads
Thread Thread Starter Forum Replies Last Post
Can two Mersenne numbers share a factor? James Heinrich Math 57 2011-09-12 14:16
Avoidance of self- & other-deception in proofs cheesehead Soap Box 71 2010-01-14 09:04
Curious and want to share about Prime number 23 spkarra PrimeNet 4 2009-11-20 03:54
Status of GIMPS proofs Brian-E Information & Answers 7 2007-08-02 23:15
Collection of Proofs? Orgasmic Troll Math 1 2004-12-30 15:10

All times are UTC. The time now is 11:57.


Sat Jul 17 11:57:01 UTC 2021 up 50 days, 9:44, 1 user, load averages: 0.96, 1.17, 1.23

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.