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Article #2667

Re: Combinatorical problem

#2667
From: Anton Greil
Date: Tue, 12 Jan 1993 09:04
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mnewman@comlab.ox.ac.uk (Matthew Newman) writes:

>Does anyone know the status on the following problem ?

>Let S(n) be the set of all permutations of the integers 1..n
>Let T(n) be the set of all transpositions (i.e. swapping
>two numbers).

>For which n can one find a set B(n) such that for all p in S(n)
>either p is in B(n), or p differs by exactly one transposition
>from an element of B(n), and such that no two elements from B(n)
>differ by exactly one transposition ?

I'd like to append with a more general question:

T(n) forms a generating system for S(n)  (for all n).
How can the combinatorics of this generating system be characterized?
Especially: does there exist a normal form of each generated element from
S(n) over the base T(n) ?

And - excuse please, yet more general - is there a connection to the general
Moebius groups of the Euclidean spaces R_n, where each such Moebius transfor-
mation can be generated by reflections, which are also elements of the
(group-) order 2 ?

Thank you!  
Toni Greil
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Path: arc1-ca.pugleaf.net!sparky!uunet!gatech!enterpoop.mit.edu!ira.uka.de!fauern!lrz-muenchen.de!regent!greil
From: greil@guug.de (Anton Greil)
Subject: Re: Combinatorical problem
Message-ID: <greil.726829446@guug.de>
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Date: Tue, 12 Jan 1993 09:04:06 GMT
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