eading GPRC: /etc/gprc ...Done.

                  GP/PARI CALCULATOR Version 2.3.1 (released)
           i486 running linux (ix86/GMP-4.2.1 kernel) 32-bit version
compiled: Nov 10 2006, gcc-4.1.2 20061103 (prerelease) (Ubuntu 4.1.1-18ubuntu2)
                (readline v5.2 enabled, extended help available)

                     Copyright (C) 2000-2006 The PARI Group

PARI/GP is free software, covered by the GNU General Public License, and 
comes WITHOUT ANY WARRANTY WHATSOEVER.

Type ? for help, \q to quit.
Type ?12 for how to get moral (and possibly technical) support.

parisize = 4000000, primelimit = 500000
? 2*3*5*7+1
%1 = 211
? isprime(%)
%2 = 1
? nextprime(300)
%3 = 307
? factor(306)
%4 = 
[2 1]

[3 2]

[17 1]

? n=%1*%3
%5 = 64777
? floor(log(n)/log(2)
  ***   expected character: ')' instead of: floor(log(n)/log(2)
                                                               ^
? floor(log(n)/log(2))
%6 = 15
? floor(log(n)/log(3))
%7 = 10
? floor(log(n)/log(5))
%8 = 6
? floor(log(n)/log(7))
%9 = 5
? Mod(2,n)^(2^15)
%10 = Mod(63134, 64777)
? gcd(63133,n)
%11 = 1
? %10^(3^10)
%12 = Mod(61058, 64777)
? gcd(lift(%)-1,n)
%13 = 1
? %12^(5^6)
%14 = Mod(36837, 64777)
? gcd(lift(%)-1,n)
%15 = 1
? %14^(7^5)
%16 = Mod(30385, 64777)
? gcd(lift(%)-1,n)
%17 = 211
? 2^8+1
%18 = 257
? isprime(%)
%19 = 1
? n=211*257
%20 = 54227
? Mod(2,n)^(2^15)
%21 = Mod(14393, 54227)
? gcd(lift(%)-1,n)
%22 = 257
? for(j=1,10,if(isprime(2^j*7+1),print(j))))
  ***   Warning: unused characters: ).
2
4
6
? n=211*(2^4*7+1)
%23 = 23843
? Mod(2,n)^(2^15)
%24 = Mod(256, 23843)
? gcd(lift(%)-1,n)
%25 = 1
? %24^(3^10)
%26 = Mod(15271, 23843)
? gcd(lift(%)-1,n)
%27 = 1
? %26^(5^6)
%28 = Mod(19113, 23843)
? gcd(lift(%)-1,n)
%29 = 1
? %28^(7^5)
%30 = Mod(1, 23843)
? gcd(lift(%)-1,n)
%31 = 23843
? Mod(2,n)^(3^10)
%32 = Mod(20665, 23843)
? gcd(lift(%)-1,n)
%33 = 1
? %32^(5^6)
%34 = Mod(11060, 23843)
? gcd(lift(%)-1,n)
%35 = 1
? %34^(7^5)
%36 = Mod(2953, 23843)
? gcd(lift(%)-1,n)
%37 = 1
? for(j=1,15,if(%36^(2^j)==Mod(1,n),print(j)))
2
3
4
5
6
7
8
9
10
11
12
13
14
15
? 536^2
%38 = 287296
? %36^2
%39 = Mod(17514, 23843)
? %^2
%40 = Mod(1, 23843)
? gcd(lift(%39)-1,n)
%41 = 211