mersenneforum.org C-PRP residue identical with different factors
 User Name Remember Me? Password
 Register FAQ Search Today's Posts Mark Forums Read

 2021-01-27, 08:14 #1 gLauss   Nov 2014 52 Posts C-PRP residue identical with different factors Hi, yesterday I did just for fun a P-1 test for the small, already factored number M3331331. This number had one known factor and two C-PRPs for the number divided by the one factor. I found a new factor, did a C-PRP for M3331331 with the two known factors and mprime reported a residue of B786DF1732AE7343. However, now this residue is also set for the C-PRP test with only 1 factor. This seems to be a bug in Primenet's logic? Last fiddled with by retina on 2021-01-27 at 09:34 Reason: Remove [bug] tag from title. It's not a bug, it's a feature
 2021-01-27, 08:42 #2 axn     Jun 2003 2×33×7×13 Posts The residue of the previous tests did not change. The residue produced is same regardless of the factors. P95 merely does another calculation at the end to see if the cofactor is a PRP and report it back if that is the case.
2021-01-27, 09:29   #3
gLauss

Nov 2014

1916 Posts

Quote:
 Originally Posted by axn The residue produced is same regardless of the factors.
Ok, this was not obvious to me. I always assumed it would calculate $3^{\frac{2^n-1}{p}} \text{ mod } \frac{2^n-1}{p}$ instead (assuming p is one or more factor). Then the residues would be different.

 Thread Tools

 Similar Threads Thread Thread Starter Forum Replies Last Post matzetoni PrimeNet 3 2019-04-07 14:00 CuriousKit PrimeNet 5 2015-04-10 01:10 GP2 Marin's Mersenne-aries 2 2007-11-19 19:03 pic_nic Linux 7 2004-11-03 08:28 jocelynl Factoring 13 2003-08-08 22:27

All times are UTC. The time now is 09:36.

Sat Apr 17 09:36:39 UTC 2021 up 9 days, 4:17, 0 users, load averages: 2.64, 2.57, 2.34

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.