Re: How do I do very big integer computing by Mathematica?

*To*: mathgroup at smc.vnet.net*Subject*: [mg115373] Re: How do I do very big integer computing by Mathematica?*From*: Daniel Lichtblau <danl at wolfram.com>*Date*: Sun, 9 Jan 2011 02:19:18 -0500 (EST)

----- Original Message ----- > From: "a boy" <avvboy at gmail.com> > To: mathgroup at smc.vnet.net > Sent: Saturday, January 8, 2011 2:37:07 AM > Subject: [mg115335] How do I do very big integer computing by Mathematica? > I'm going to search big Fibonacci prime numbers. I think there is a > simple primality test algorithm for Fibonacci number, like Lucas=96 > Lehmer primality test for 2^n-1 . I'm lazy and don't want to write > many codes. So i want to ask: > > p=43,112,609; > s[0]=4; > s[n_]:=s[n-1]^2-4 > pt=Mod[s[p-2], 2^p-1]==0 > > how do I compute s[43,112,609-2] directly? It seems the largest > integer in M~ is 2^32^32, isn't it? Not exactly certain what you want to do from that description. But something that might help is to interleave Mod[] operations provided the modulus is not too large for Mathematica. Daniel Lichtblau Wolfram Research