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Article #135

Permutation Polytopes

#135
From: Michael Cohen
Date: Sat, 03 Oct 1992 01:26
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Treat the orderings on n letters as permutations.
For each ordering a, define a point in n X n-1/2
space as follows.

U_a(i,j) = 1 if i a j
U_a(i,j) = -1 otherwise.

Consider the convex polytope U which is a convex combination of these
extreme points.  Question:  What is the polar polyhedron.  i.e. the
extreme points of the the of elements <l, u> <= 1. for all u in U.
            -mike



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Boston University (617-353-7857) Email: mike@park.bu.edu
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From: mike@park.bu.edu (Michael Cohen)
Newsgroups: sci.math.research
Subject: Permutation Polytopes
Summary: Polytopes, extreme points
Keywords: Extreme points
Message-ID: <97468@bu.edu>
Date: 3 Oct 92 01:26:16 GMT
References: <FRANK.92Sep18140543@ae.ae.tut.fi>
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