Cubical Convex Ear Decompositions
نویسندگان
چکیده
منابع مشابه
Cubical Convex Ear Decompositions
We consider the problem of constructing a convex ear decomposition for a poset. The usual technique, introduced by Nyman and Swartz, starts with a CL-labeling and uses this to shell the ‘ears’ of the decomposition. We axiomatize the necessary conditions for this technique as a “CL-ced” or “EL-ced”. We find an EL-ced of the d-divisible partition lattice, and a closely related convex ear decompos...
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We prove a theorem allowing us to find convex-ear decompositions for rankselected subposets of posets that are unions of Boolean sublattices in a coherent fashion. We then apply this theorem to geometric lattices and face posets of shellable complexes, obtaining new inequalities for their h-vectors. Finally, we use the latter decomposition to give a new interpretation to inequalities satisfied ...
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ژورنال
عنوان ژورنال: The Electronic Journal of Combinatorics
سال: 2009
ISSN: 1077-8926
DOI: 10.37236/83