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From: agn@unh.cs.cmu.edu (Andreas Nowatzyk)
Newsgroups: sci.crypt
Subject: Re: Random number generation
Message-ID: <1610@pt.cs.cmu.edu>
Date: 5 May 88 08:42:35 GMT
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Organization: Carnegie-Mellon University, CS/RI
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The shift & xor - way of generating not-very-random numbers requires
more that 2 taps for certain numbers of bits in order to get the max.
period lengh (=2^n - 1). A table of polynomials that require only 2
terms can be found in Knuth's "The Art of Computer Programming", Vol.2.

There is no 2-term solution for either 16, 32, 48 or 64 bit.
(3, 17), (7, 31), (5, 47), (1, 63)  are some nearby generators.
-- 
   --  Andreas Nowatzyk  (DC5ZV)

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