Algebraic Shifting and Sequentially Cohen-Macaulay Simplicial Complexes
نویسندگان
چکیده
منابع مشابه
Algebraic Shifting and Sequentially Cohen-Macaulay Simplicial Complexes
Björner and Wachs generalized the definition of shellability by dropping the assumption of purity; they also introduced the h-triangle, a doubly-indexed generalization of the h-vector which is combinatorially significant for nonpure shellable complexes. Stanley subsequently defined a nonpure simplicial complex to be sequentially Cohen-Macaulay if it satisfies algebraic conditions that generaliz...
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The classes of sequentially Cohen-Macaulay and sequentially homotopy Cohen-Macaulay complexes and posets are studied. First, some different versions of the definitions are discussed and the homotopy type is determined. Second, it is shown how various constructions, such as join, product and rank-selection preserve these properties. Third, a characterization of sequential Cohen-Macaulayness for ...
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ژورنال
عنوان ژورنال: The Electronic Journal of Combinatorics
سال: 1996
ISSN: 1077-8926
DOI: 10.37236/1245