A generating function for all semi-magic squares and the volume of the Birkhoff polytope

نویسندگان

  • J. A. De Loera
  • R. Yoshida
چکیده

We present a multivariate generating function for all n × n nonnegative integral matrices with all row and column sums equal to a positive integer t , the so called semi-magic squares. As a consequence we obtain formulas for all coefficients of the Ehrhart polynomial of the polytope Bn of n×n doubly-stochastic matrices, also known as the Birkhoff polytope. In particular we derive formulas for the volumes of Bn and any of its faces.

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تاریخ انتشار 2008