Permutation polytopes corresponding to strongly supermodular functions

نویسندگان

  • Frank K. Hwang
  • J. S. Lee
  • Uriel G. Rothblum
چکیده

Throughout, let p be a positive integer and let be the set of permutations over {1; : : : ; p}. A real-valued function over subsets of {1; : : : ; p}, with (∅)=0, de7nes a mapping of into R where ∈ is mapped into the vector whose kth coordinate ( )k is the augmented -value obtained from adding k to the coordinates that precede it, according to the ranking induced by . The permutation polytope corresponding to is then the convex hull of the vectors corresponding to all permutations. We introduce a new class of strongly supermodular functions and for such functions we derive an isomorphic representation for the face-lattices of the corresponding permutation polytope. c © 2003 Elsevier B.V. All rights reserved.

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عنوان ژورنال:
  • Discrete Applied Mathematics

دوره 142  شماره 

صفحات  -

تاریخ انتشار 2004