substitution boxes and such

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Article #1347

#1347

From: Jeffrey Frey P730
Date: Fri, 21 Apr 1995 00:00

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Hi

I would like to build an efficent counter that will sequence
thru all of it's unique states in as many ways as possible
(without repeating any) via some sort of seed or control mechanism. 

I am not a mathematician (and I may really embarrass myself here :))
but I *believe* there are (2^n)! possible unique sequences for a n bit 
counter; ie. 40320 possbile unique (8 state) sequences for 
a 3 bit counter. That's a large LUT using a brute force approach.

Anyone have any slick tricks (algorithms) for achieving a 
high number different sequneces, efficently?

Please reply to (or copy) jfrey@bnr.ca as I am not a regular 
subscriber to this news group.

thanks

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From: Jeffrey Frey P730 <jfrey@bnr.ca>
Subject: substitution boxes and such
Date: 1995/04/21
Message-ID: <3n8tm2$n21@brtph500.bnr.ca>
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organization: Bell Northern Research
newsgroups: comp.lsi,comp.dsp,can.vlsi,alt.info-theory,comp.security.misc