Go Back > New To GIMPS? Start Here! > Information & Answers

Thread Tools
Old 2016-01-29, 03:02   #1
Dec 2014

3×5×17 Posts
Default M39761383 history

One of my machines recently finished a double check and apparently
the residue did not match. I go look at the details for this exponent

and it has had three LL tests run and none of the residues match.
Does this happen a lot?

Trivia question: Which exponent has had the most number of
(unmatching residue) LL tests done on it? (I don't know.)
bgbeuning is offline   Reply With Quote
Old 2016-01-29, 03:08   #2
Mark Rose
Mark Rose's Avatar
Jan 2013

37·79 Posts

It happens often enough. It's not unusual to need a quad check.
Mark Rose is offline   Reply With Quote
Old 2016-01-29, 03:19   #3
Basketry That Evening!
Dubslow's Avatar
"Bunslow the Bold"
Jun 2011
40<A<43 -89<O<-88

3×29×83 Posts

Most or all of those questions have been answered at some point in time in this thread:

Of course, I couldn't tell you *where* in the thread the answers lie. Perhaps madpoo would have better luck refreshing our memories.

Suffice it to say, as Mark indicates, quad checks are surprisingly common, I think more than 10 per 1M exponent range, possibly even up to a hundred.

I think the most mismatches is somewhere around 6, though I may be recalling incorrectly.
Dubslow is offline   Reply With Quote

Thread Tools

Similar Threads
Thread Thread Starter Forum Replies Last Post
A question of history devarajkandadai Number Theory Discussion Group 8 2017-06-01 13:15
Cranks of History Mini-Geek Miscellaneous Math 1 2016-04-01 12:36
History ET_ Operazione Doppi Mersennes 15 2012-09-19 13:11
History Greenbank Octoproth Search 1 2007-02-16 23:41
History of 3*2^n-1 Citrix 3*2^n-1 Search 2 2006-11-16 00:13

All times are UTC. The time now is 07:50.

Mon Nov 29 07:50:03 UTC 2021 up 129 days, 2:19, 0 users, load averages: 0.76, 0.82, 0.80

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.