A combinatorial decomposition of acyclic simplicial complexes
نویسنده
چکیده
Stanley, R.P., A combinatorial decomposition of acyclic simplicial complexes, Discrete Mathematics 120 (1993) 175-182. It is proved that if d is a finite acyclic simplicial complex, then there is a subcomplex d’ c d and a bijection q:d’+d-d’ such that Fcq(F) and /q(F)-FJ=l for all FEN’. This improves an earlier result of Kalai. An immediate corollary is a characterization (first due to Kalai) of the f-vector of an acyclic simplicial complex. Several generalizations, some proved and some conjectured, are discussed.
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عنوان ژورنال:
- Discrete Mathematics
دوره 120 شماره
صفحات -
تاریخ انتشار 1993