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\noindent
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{\bf Torsten Ekedahl}
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{\bf Shellability of a Poset of Polygonal Subdivisions}
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We introduce a sequence of posets closely related to the
associahedra. In this we are motivated by reasons similar to those of
Stasheff in the case of the associahedra. We make a study of this
poset showing that it has an inductive structure with proper downwards
intervals being products of smaller posets in the same series and
associahedra. Using this we also show that they are thin dual
CL-shellable and in particular that they are the face poset of a
regular cell decomposition of the ball.

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