The cd-index of zonotopes and arrangements

نویسندگان

  • Louis J. Billera
  • Richard Ehrenborg
  • Margaret Readdy
چکیده

We investigate a special class of polytopes, the zonotopes, and show that their flag f -vectors satisfy only the affine relations fulfilled by flag f -vectors of all polytopes. In addition, we determine the lattice spanned by flag f -vectors of zonotopes. By duality, these results apply as well to the flag f -vectors of central arrangements of hyperplanes.

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تاریخ انتشار 1998