20040126, 21:37  #12 
2×2,251 Posts 
Primality tests
I understand you need some code to implement in a computer program. please specify the OS platform and programming language you preffer to work with and i'll see what i can do.
From what i gather you need to test primes up to 20 digits, is this correct? Please reply here or at the user forum at www.shteker.com 
20040126, 21:51  #13 
Nov 2002
2×37 Posts 
I'm using win98 and c++
mostly i wirte my programs with the help of the MIRACL libary or the giantint library 
20040127, 05:07  #14 
Sep 2002
2·331 Posts 
Some basic background information on trial factoring.
Only need to test to the square root of the number. For numbers expressed in base ten the square root will be at most one more than half the number of digits as the number your trying to factor. A 15 digit number would have 8 digits max for the square root. All primes except 2 and 3 are 6x +/ 1 with x = 1 ... so the factor mod 6 must be either 1 or 5 to be a potential prime. A 64 bit unsigned integer can hold a 20 digit number (18446744073709551615 max). 
20040127, 14:35  #15 
Nov 2002
74_{10} Posts 
but trial factoring a 20 digit number take a while!!!
I want to implement a primility test where i know theat the number is 100% prime!!! 
20040127, 17:21  #16  
∂^{2}ω=0
Sep 2002
República de California
2D69_{16} Posts 
Quote:


Thread Tools  
Similar Threads  
Thread  Thread Starter  Forum  Replies  Last Post 
Antipoverty drug testing vs "high" tax deduction testing  kladner  Soap Box  3  20161014 18:43 
PRP testing  pepi37  Software  6  20130412 09:42 
Testing  grobie  Marin's Mersennearies  1  20060515 12:26 
Speed of P1 testing vs. Trial Factoring testing  eepiccolo  Math  6  20060328 20:53 
P1 Testing  ndpowell  Math  4  20050626 20:14 